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RocksDB fat jar that contains .so files for linux32 and linux64 (glibc and musl-libc), jnilib files
for Mac OSX, and a .dll for Windows x64.
The newest version!
// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under both the GPLv2 (found in the
// COPYING file in the root directory) and Apache 2.0 License
// (found in the LICENSE.Apache file in the root directory).
package org.rocksdb;
import java.util.Collection;
import java.util.List;
public interface DBOptionsInterface> {
/**
* Use this if your DB is very small (like under 1GB) and you don't want to
* spend lots of memory for memtables.
*
* @return the instance of the current object.
*/
T optimizeForSmallDb();
/**
* Use the specified object to interact with the environment,
* e.g. to read/write files, schedule background work, etc.
* Default: {@link Env#getDefault()}
*
* @param env {@link Env} instance.
* @return the instance of the current Options.
*/
T setEnv(final Env env);
/**
* Returns the set RocksEnv instance.
*
* @return {@link RocksEnv} instance set in the options.
*/
Env getEnv();
/**
* By default, RocksDB uses only one background thread for flush and
* compaction. Calling this function will set it up such that total of
* `total_threads` is used.
*
* You almost definitely want to call this function if your system is
* bottlenecked by RocksDB.
*
* @param totalThreads The total number of threads to be used by RocksDB.
* A good value is the number of cores.
*
* @return the instance of the current Options
*/
T setIncreaseParallelism(int totalThreads);
/**
* If this value is set to true, then the database will be created
* if it is missing during {@code RocksDB.open()}.
* Default: false
*
* @param flag a flag indicating whether to create a database the
* specified database in {@link RocksDB#open(org.rocksdb.Options, String)} operation
* is missing.
* @return the instance of the current Options
* @see RocksDB#open(org.rocksdb.Options, String)
*/
T setCreateIfMissing(boolean flag);
/**
* Return true if the create_if_missing flag is set to true.
* If true, the database will be created if it is missing.
*
* @return true if the createIfMissing option is set to true.
* @see #setCreateIfMissing(boolean)
*/
boolean createIfMissing();
/**
* If true, missing column families will be automatically created
*
* Default: false
*
* @param flag a flag indicating if missing column families shall be
* created automatically.
* @return true if missing column families shall be created automatically
* on open.
*/
T setCreateMissingColumnFamilies(boolean flag);
/**
* Return true if the create_missing_column_families flag is set
* to true. If true column families be created if missing.
*
* @return true if the createMissingColumnFamilies is set to
* true.
* @see #setCreateMissingColumnFamilies(boolean)
*/
boolean createMissingColumnFamilies();
/**
* If true, an error will be thrown during RocksDB.open() if the
* database already exists.
* Default: false
*
* @param errorIfExists if true, an exception will be thrown
* during {@code RocksDB.open()} if the database already exists.
* @return the reference to the current option.
* @see RocksDB#open(org.rocksdb.Options, String)
*/
T setErrorIfExists(boolean errorIfExists);
/**
* If true, an error will be thrown during RocksDB.open() if the
* database already exists.
*
* @return if true, an error is raised when the specified database
* already exists before open.
*/
boolean errorIfExists();
/**
* If true, the implementation will do aggressive checking of the
* data it is processing and will stop early if it detects any
* errors. This may have unforeseen ramifications: for example, a
* corruption of one DB entry may cause a large number of entries to
* become unreadable or for the entire DB to become unopenable.
* If any of the writes to the database fails (Put, Delete, Merge, Write),
* the database will switch to read-only mode and fail all other
* Write operations.
* Default: true
*
* @param paranoidChecks a flag to indicate whether paranoid-check
* is on.
* @return the reference to the current option.
*/
T setParanoidChecks(boolean paranoidChecks);
/**
* If true, the implementation will do aggressive checking of the
* data it is processing and will stop early if it detects any
* errors. This may have unforeseen ramifications: for example, a
* corruption of one DB entry may cause a large number of entries to
* become unreadable or for the entire DB to become unopenable.
* If any of the writes to the database fails (Put, Delete, Merge, Write),
* the database will switch to read-only mode and fail all other
* Write operations.
*
* @return a boolean indicating whether paranoid-check is on.
*/
boolean paranoidChecks();
/**
* Use to control write rate of flush and compaction. Flush has higher
* priority than compaction. Rate limiting is disabled if nullptr.
* Default: nullptr
*
* @param rateLimiter {@link org.rocksdb.RateLimiter} instance.
* @return the instance of the current object.
*
* @since 3.10.0
*/
T setRateLimiter(RateLimiter rateLimiter);
/**
* Use to track SST files and control their file deletion rate.
*
* Features:
* - Throttle the deletion rate of the SST files.
* - Keep track the total size of all SST files.
* - Set a maximum allowed space limit for SST files that when reached
* the DB wont do any further flushes or compactions and will set the
* background error.
* - Can be shared between multiple dbs.
*
* Limitations:
* - Only track and throttle deletes of SST files in
* first db_path (db_name if db_paths is empty).
*
* @param sstFileManager The SST File Manager for the db.
* @return the instance of the current object.
*/
T setSstFileManager(SstFileManager sstFileManager);
/**
* Any internal progress/error information generated by
* the db will be written to the Logger if it is non-nullptr,
* or to a file stored in the same directory as the DB
* contents if info_log is nullptr.
*
* Default: nullptr
*
* @param logger {@link Logger} instance.
* @return the instance of the current object.
*/
T setLogger(Logger logger);
/**
* Sets the RocksDB log level. Default level is INFO
*
* @param infoLogLevel log level to set.
* @return the instance of the current object.
*/
T setInfoLogLevel(InfoLogLevel infoLogLevel);
/**
* Returns currently set log level.
* @return {@link org.rocksdb.InfoLogLevel} instance.
*/
InfoLogLevel infoLogLevel();
/**
* If {@link MutableDBOptionsInterface#maxOpenFiles()} is -1, DB will open
* all files on DB::Open(). You can use this option to increase the number
* of threads used to open the files.
*
* Default: 16
*
* @param maxFileOpeningThreads the maximum number of threads to use to
* open files
*
* @return the reference to the current options.
*/
T setMaxFileOpeningThreads(int maxFileOpeningThreads);
/**
* If {@link MutableDBOptionsInterface#maxOpenFiles()} is -1, DB will open all
* files on DB::Open(). You can use this option to increase the number of
* threads used to open the files.
*
* Default: 16
*
* @return the maximum number of threads to use to open files
*/
int maxFileOpeningThreads();
/**
* Sets the statistics object which collects metrics about database operations.
* Statistics objects should not be shared between DB instances as
* it does not use any locks to prevent concurrent updates.
*
* @param statistics The statistics to set
*
* @return the instance of the current object.
*
* @see RocksDB#open(org.rocksdb.Options, String)
*/
T setStatistics(final Statistics statistics);
/**
* Returns statistics object.
*
* @return the instance of the statistics object or null if there is no
* statistics object.
*
* @see #setStatistics(Statistics)
*/
Statistics statistics();
/**
* If true, then every store to stable storage will issue a fsync.
* If false, then every store to stable storage will issue a fdatasync.
* This parameter should be set to true while storing data to
* filesystem like ext3 that can lose files after a reboot.
* Default: false
*
* @param useFsync a boolean flag to specify whether to use fsync
* @return the instance of the current object.
*/
T setUseFsync(boolean useFsync);
/**
* If true, then every store to stable storage will issue a fsync.
* If false, then every store to stable storage will issue a fdatasync.
* This parameter should be set to true while storing data to
* filesystem like ext3 that can lose files after a reboot.
*
* @return boolean value indicating if fsync is used.
*/
boolean useFsync();
/**
* A list of paths where SST files can be put into, with its target size.
* Newer data is placed into paths specified earlier in the vector while
* older data gradually moves to paths specified later in the vector.
*
* For example, you have a flash device with 10GB allocated for the DB,
* as well as a hard drive of 2TB, you should config it to be:
* [{"/flash_path", 10GB}, {"/hard_drive", 2TB}]
*
* The system will try to guarantee data under each path is close to but
* not larger than the target size. But current and future file sizes used
* by determining where to place a file are based on best-effort estimation,
* which means there is a chance that the actual size under the directory
* is slightly more than target size under some workloads. User should give
* some buffer room for those cases.
*
* If none of the paths has sufficient room to place a file, the file will
* be placed to the last path anyway, despite to the target size.
*
* Placing newer data to earlier paths is also best-efforts. User should
* expect user files to be placed in higher levels in some extreme cases.
*
* If left empty, only one path will be used, which is db_name passed when
* opening the DB.
*
* Default: empty
*
* @param dbPaths the paths and target sizes
*
* @return the reference to the current options
*/
T setDbPaths(final Collection dbPaths);
/**
* A list of paths where SST files can be put into, with its target size.
* Newer data is placed into paths specified earlier in the vector while
* older data gradually moves to paths specified later in the vector.
*
* For example, you have a flash device with 10GB allocated for the DB,
* as well as a hard drive of 2TB, you should config it to be:
* [{"/flash_path", 10GB}, {"/hard_drive", 2TB}]
*
* The system will try to guarantee data under each path is close to but
* not larger than the target size. But current and future file sizes used
* by determining where to place a file are based on best-effort estimation,
* which means there is a chance that the actual size under the directory
* is slightly more than target size under some workloads. User should give
* some buffer room for those cases.
*
* If none of the paths has sufficient room to place a file, the file will
* be placed to the last path anyway, despite to the target size.
*
* Placing newer data to earlier paths is also best-efforts. User should
* expect user files to be placed in higher levels in some extreme cases.
*
* If left empty, only one path will be used, which is db_name passed when
* opening the DB.
*
* Default: {@link java.util.Collections#emptyList()}
*
* @return dbPaths the paths and target sizes
*/
List dbPaths();
/**
* This specifies the info LOG dir.
* If it is empty, the log files will be in the same dir as data.
* If it is non empty, the log files will be in the specified dir,
* and the db data dir's absolute path will be used as the log file
* name's prefix.
*
* @param dbLogDir the path to the info log directory
* @return the instance of the current object.
*/
T setDbLogDir(String dbLogDir);
/**
* Returns the directory of info log.
*
* If it is empty, the log files will be in the same dir as data.
* If it is non empty, the log files will be in the specified dir,
* and the db data dir's absolute path will be used as the log file
* name's prefix.
*
* @return the path to the info log directory
*/
String dbLogDir();
/**
* This specifies the absolute dir path for write-ahead logs (WAL).
* If it is empty, the log files will be in the same dir as data,
* dbname is used as the data dir by default
* If it is non empty, the log files will be in kept the specified dir.
* When destroying the db,
* all log files in wal_dir and the dir itself is deleted
*
* @param walDir the path to the write-ahead-log directory.
* @return the instance of the current object.
*/
T setWalDir(String walDir);
/**
* Returns the path to the write-ahead-logs (WAL) directory.
*
* If it is empty, the log files will be in the same dir as data,
* dbname is used as the data dir by default
* If it is non empty, the log files will be in kept the specified dir.
* When destroying the db,
* all log files in wal_dir and the dir itself is deleted
*
* @return the path to the write-ahead-logs (WAL) directory.
*/
String walDir();
/**
* The periodicity when obsolete files get deleted. The default
* value is 6 hours. The files that get out of scope by compaction
* process will still get automatically delete on every compaction,
* regardless of this setting
*
* @param micros the time interval in micros
* @return the instance of the current object.
*/
T setDeleteObsoleteFilesPeriodMicros(long micros);
/**
* The periodicity when obsolete files get deleted. The default
* value is 6 hours. The files that get out of scope by compaction
* process will still get automatically delete on every compaction,
* regardless of this setting
*
* @return the time interval in micros when obsolete files will be deleted.
*/
long deleteObsoleteFilesPeriodMicros();
/**
* This value represents the maximum number of threads that will
* concurrently perform a compaction job by breaking it into multiple,
* smaller ones that are run simultaneously.
* Default: 1 (i.e. no subcompactions)
*
* @param maxSubcompactions The maximum number of threads that will
* concurrently perform a compaction job
*
* @return the instance of the current object.
*/
T setMaxSubcompactions(int maxSubcompactions);
/**
* This value represents the maximum number of threads that will
* concurrently perform a compaction job by breaking it into multiple,
* smaller ones that are run simultaneously.
* Default: 1 (i.e. no subcompactions)
*
* @return The maximum number of threads that will concurrently perform a
* compaction job
*/
int maxSubcompactions();
/**
* NOT SUPPORTED ANYMORE: RocksDB automatically decides this based on the
* value of max_background_jobs. For backwards compatibility we will set
* `max_background_jobs = max_background_compactions + max_background_flushes`
* in the case where user sets at least one of `max_background_compactions` or
* `max_background_flushes`.
*
* Specifies the maximum number of concurrent background flush jobs.
* If you're increasing this, also consider increasing number of threads in
* HIGH priority thread pool. For more information, see
* Default: -1
*
* @param maxBackgroundFlushes number of max concurrent flush jobs
* @return the instance of the current object.
*
* @see RocksEnv#setBackgroundThreads(int)
* @see RocksEnv#setBackgroundThreads(int, Priority)
* @see MutableDBOptionsInterface#maxBackgroundCompactions()
*
* @deprecated Use {@link MutableDBOptionsInterface#setMaxBackgroundJobs(int)}
*/
@Deprecated
T setMaxBackgroundFlushes(int maxBackgroundFlushes);
/**
* NOT SUPPORTED ANYMORE: RocksDB automatically decides this based on the
* value of max_background_jobs. For backwards compatibility we will set
* `max_background_jobs = max_background_compactions + max_background_flushes`
* in the case where user sets at least one of `max_background_compactions` or
* `max_background_flushes`.
*
* Returns the maximum number of concurrent background flush jobs.
* If you're increasing this, also consider increasing number of threads in
* HIGH priority thread pool. For more information, see
* Default: -1
*
* @return the maximum number of concurrent background flush jobs.
* @see RocksEnv#setBackgroundThreads(int)
* @see RocksEnv#setBackgroundThreads(int, Priority)
*/
@Deprecated
int maxBackgroundFlushes();
/**
* Specifies the maximum size of a info log file. If the current log file
* is larger than `max_log_file_size`, a new info log file will
* be created.
* If 0, all logs will be written to one log file.
*
* @param maxLogFileSize the maximum size of a info log file.
* @return the instance of the current object.
* @throws java.lang.IllegalArgumentException thrown on 32-Bit platforms
* while overflowing the underlying platform specific value.
*/
T setMaxLogFileSize(long maxLogFileSize);
/**
* Returns the maximum size of a info log file. If the current log file
* is larger than this size, a new info log file will be created.
* If 0, all logs will be written to one log file.
*
* @return the maximum size of the info log file.
*/
long maxLogFileSize();
/**
* Specifies the time interval for the info log file to roll (in seconds).
* If specified with non-zero value, log file will be rolled
* if it has been active longer than `log_file_time_to_roll`.
* Default: 0 (disabled)
*
* @param logFileTimeToRoll the time interval in seconds.
* @return the instance of the current object.
* @throws java.lang.IllegalArgumentException thrown on 32-Bit platforms
* while overflowing the underlying platform specific value.
*/
T setLogFileTimeToRoll(long logFileTimeToRoll);
/**
* Returns the time interval for the info log file to roll (in seconds).
* If specified with non-zero value, log file will be rolled
* if it has been active longer than `log_file_time_to_roll`.
* Default: 0 (disabled)
*
* @return the time interval in seconds.
*/
long logFileTimeToRoll();
/**
* Specifies the maximum number of info log files to be kept.
* Default: 1000
*
* @param keepLogFileNum the maximum number of info log files to be kept.
* @return the instance of the current object.
* @throws java.lang.IllegalArgumentException thrown on 32-Bit platforms
* while overflowing the underlying platform specific value.
*/
T setKeepLogFileNum(long keepLogFileNum);
/**
* Returns the maximum number of info log files to be kept.
* Default: 1000
*
* @return the maximum number of info log files to be kept.
*/
long keepLogFileNum();
/**
* Recycle log files.
*
* If non-zero, we will reuse previously written log files for new
* logs, overwriting the old data. The value indicates how many
* such files we will keep around at any point in time for later
* use.
*
* This is more efficient because the blocks are already
* allocated and fdatasync does not need to update the inode after
* each write.
*
* Default: 0
*
* @param recycleLogFileNum the number of log files to keep for recycling
*
* @return the reference to the current options
*/
T setRecycleLogFileNum(long recycleLogFileNum);
/**
* Recycle log files.
*
* If non-zero, we will reuse previously written log files for new
* logs, overwriting the old data. The value indicates how many
* such files we will keep around at any point in time for later
* use.
*
* This is more efficient because the blocks are already
* allocated and fdatasync does not need to update the inode after
* each write.
*
* Default: 0
*
* @return the number of log files kept for recycling
*/
long recycleLogFileNum();
/**
* Manifest file is rolled over on reaching this limit.
* The older manifest file be deleted.
* The default value is 1GB so that the manifest file can grow, but not
* reach the limit of storage capacity.
*
* @param maxManifestFileSize the size limit of a manifest file.
* @return the instance of the current object.
*/
T setMaxManifestFileSize(long maxManifestFileSize);
/**
* Manifest file is rolled over on reaching this limit.
* The older manifest file be deleted.
* The default value is 1GB so that the manifest file can grow, but not
* reach the limit of storage capacity.
*
* @return the size limit of a manifest file.
*/
long maxManifestFileSize();
/**
* Number of shards used for table cache.
*
* @param tableCacheNumshardbits the number of chards
* @return the instance of the current object.
*/
T setTableCacheNumshardbits(int tableCacheNumshardbits);
/**
* Number of shards used for table cache.
*
* @return the number of shards used for table cache.
*/
int tableCacheNumshardbits();
/**
* {@link #walTtlSeconds()} and {@link #walSizeLimitMB()} affect how archived logs
* will be deleted.
*
* - If both set to 0, logs will be deleted asap and will not get into
* the archive.
* - If WAL_ttl_seconds is 0 and WAL_size_limit_MB is not 0,
* WAL files will be checked every 10 min and if total size is greater
* then WAL_size_limit_MB, they will be deleted starting with the
* earliest until size_limit is met. All empty files will be deleted.
* - If WAL_ttl_seconds is not 0 and WAL_size_limit_MB is 0, then
* WAL files will be checked every WAL_ttl_secondsi / 2 and those that
* are older than WAL_ttl_seconds will be deleted.
* - If both are not 0, WAL files will be checked every 10 min and both
* checks will be performed with ttl being first.
*
*
* @param walTtlSeconds the ttl seconds
* @return the instance of the current object.
* @see #setWalSizeLimitMB(long)
*/
T setWalTtlSeconds(long walTtlSeconds);
/**
* WalTtlSeconds() and walSizeLimitMB() affect how archived logs
* will be deleted.
*
* - If both set to 0, logs will be deleted asap and will not get into
* the archive.
* - If WAL_ttl_seconds is 0 and WAL_size_limit_MB is not 0,
* WAL files will be checked every 10 min and if total size is greater
* then WAL_size_limit_MB, they will be deleted starting with the
* earliest until size_limit is met. All empty files will be deleted.
* - If WAL_ttl_seconds is not 0 and WAL_size_limit_MB is 0, then
* WAL files will be checked every WAL_ttl_secondsi / 2 and those that
* are older than WAL_ttl_seconds will be deleted.
* - If both are not 0, WAL files will be checked every 10 min and both
* checks will be performed with ttl being first.
*
*
* @return the wal-ttl seconds
* @see #walSizeLimitMB()
*/
long walTtlSeconds();
/**
* WalTtlSeconds() and walSizeLimitMB() affect how archived logs
* will be deleted.
*
* - If both set to 0, logs will be deleted asap and will not get into
* the archive.
* - If WAL_ttl_seconds is 0 and WAL_size_limit_MB is not 0,
* WAL files will be checked every 10 min and if total size is greater
* then WAL_size_limit_MB, they will be deleted starting with the
* earliest until size_limit is met. All empty files will be deleted.
* - If WAL_ttl_seconds is not 0 and WAL_size_limit_MB is 0, then
* WAL files will be checked every WAL_ttl_secondsi / 2 and those that
* are older than WAL_ttl_seconds will be deleted.
* - If both are not 0, WAL files will be checked every 10 min and both
* checks will be performed with ttl being first.
*
*
* @param sizeLimitMB size limit in mega-bytes.
* @return the instance of the current object.
* @see #setWalSizeLimitMB(long)
*/
T setWalSizeLimitMB(long sizeLimitMB);
/**
* {@link #walTtlSeconds()} and {@code #walSizeLimitMB()} affect how archived logs
* will be deleted.
*
* - If both set to 0, logs will be deleted asap and will not get into
* the archive.
* - If WAL_ttl_seconds is 0 and WAL_size_limit_MB is not 0,
* WAL files will be checked every 10 min and if total size is greater
* then WAL_size_limit_MB, they will be deleted starting with the
* earliest until size_limit is met. All empty files will be deleted.
* - If WAL_ttl_seconds is not 0 and WAL_size_limit_MB is 0, then
* WAL files will be checked every WAL_ttl_seconds i / 2 and those that
* are older than WAL_ttl_seconds will be deleted.
* - If both are not 0, WAL files will be checked every 10 min and both
* checks will be performed with ttl being first.
*
* @return size limit in mega-bytes.
* @see #walSizeLimitMB()
*/
long walSizeLimitMB();
/**
* The maximum limit of number of bytes that are written in a single batch
* of WAL or memtable write. It is followed when the leader write size
* is larger than 1/8 of this limit.
*
* Default: 1 MB
*
* @param maxWriteBatchGroupSizeBytes the maximum limit of number of bytes, see description.
* @return the instance of the current object.
*/
T setMaxWriteBatchGroupSizeBytes(final long maxWriteBatchGroupSizeBytes);
/**
* The maximum limit of number of bytes that are written in a single batch
* of WAL or memtable write. It is followed when the leader write size
* is larger than 1/8 of this limit.
*
* Default: 1 MB
*
* @return the maximum limit of number of bytes, see description.
*/
long maxWriteBatchGroupSizeBytes();
/**
* Number of bytes to preallocate (via fallocate) the manifest
* files. Default is 4mb, which is reasonable to reduce random IO
* as well as prevent overallocation for mounts that preallocate
* large amounts of data (such as xfs's allocsize option).
*
* @param size the size in byte
* @return the instance of the current object.
* @throws java.lang.IllegalArgumentException thrown on 32-Bit platforms
* while overflowing the underlying platform specific value.
*/
T setManifestPreallocationSize(long size);
/**
* Number of bytes to preallocate (via fallocate) the manifest
* files. Default is 4mb, which is reasonable to reduce random IO
* as well as prevent overallocation for mounts that preallocate
* large amounts of data (such as xfs's allocsize option).
*
* @return size in bytes.
*/
long manifestPreallocationSize();
/**
* Enable the OS to use direct I/O for reading sst tables.
* Default: false
*
* @param useDirectReads if true, then direct read is enabled
* @return the instance of the current object.
*/
T setUseDirectReads(boolean useDirectReads);
/**
* Enable the OS to use direct I/O for reading sst tables.
* Default: false
*
* @return if true, then direct reads are enabled
*/
boolean useDirectReads();
/**
* Enable the OS to use direct reads and writes in flush and
* compaction
* Default: false
*
* @param useDirectIoForFlushAndCompaction if true, then direct
* I/O will be enabled for background flush and compactions
* @return the instance of the current object.
*/
T setUseDirectIoForFlushAndCompaction(boolean useDirectIoForFlushAndCompaction);
/**
* Enable the OS to use direct reads and writes in flush and
* compaction
*
* @return if true, then direct I/O is enabled for flush and
* compaction
*/
boolean useDirectIoForFlushAndCompaction();
/**
* Whether fallocate calls are allowed
*
* @param allowFAllocate false if fallocate() calls are bypassed
*
* @return the reference to the current options.
*/
T setAllowFAllocate(boolean allowFAllocate);
/**
* Whether fallocate calls are allowed
*
* @return false if fallocate() calls are bypassed
*/
boolean allowFAllocate();
/**
* Allow the OS to mmap file for reading sst tables.
* Default: false
*
* @param allowMmapReads true if mmap reads are allowed.
* @return the instance of the current object.
*/
T setAllowMmapReads(boolean allowMmapReads);
/**
* Allow the OS to mmap file for reading sst tables.
* Default: false
*
* @return true if mmap reads are allowed.
*/
boolean allowMmapReads();
/**
* Allow the OS to mmap file for writing. Default: false
*
* @param allowMmapWrites true if mmap writes are allowd.
* @return the instance of the current object.
*/
T setAllowMmapWrites(boolean allowMmapWrites);
/**
* Allow the OS to mmap file for writing. Default: false
*
* @return true if mmap writes are allowed.
*/
boolean allowMmapWrites();
/**
* Disable child process inherit open files. Default: true
*
* @param isFdCloseOnExec true if child process inheriting open
* files is disabled.
* @return the instance of the current object.
*/
T setIsFdCloseOnExec(boolean isFdCloseOnExec);
/**
* Disable child process inherit open files. Default: true
*
* @return true if child process inheriting open files is disabled.
*/
boolean isFdCloseOnExec();
/**
* If set true, will hint the underlying file system that the file
* access pattern is random, when a sst file is opened.
* Default: true
*
* @param adviseRandomOnOpen true if hinting random access is on.
* @return the instance of the current object.
*/
T setAdviseRandomOnOpen(boolean adviseRandomOnOpen);
/**
* If set true, will hint the underlying file system that the file
* access pattern is random, when a sst file is opened.
* Default: true
*
* @return true if hinting random access is on.
*/
boolean adviseRandomOnOpen();
/**
* Amount of data to build up in memtables across all column
* families before writing to disk.
*
* This is distinct from {@link ColumnFamilyOptions#writeBufferSize()},
* which enforces a limit for a single memtable.
*
* This feature is disabled by default. Specify a non-zero value
* to enable it.
*
* Default: 0 (disabled)
*
* @param dbWriteBufferSize the size of the write buffer
*
* @return the reference to the current options.
*/
T setDbWriteBufferSize(long dbWriteBufferSize);
/**
* Use passed {@link WriteBufferManager} to control memory usage across
* multiple column families and/or DB instances.
*
* Check
* https://github.com/facebook/rocksdb/wiki/Write-Buffer-Manager
* for more details on when to use it
*
* @param writeBufferManager The WriteBufferManager to use
* @return the reference of the current options.
*/
T setWriteBufferManager(final WriteBufferManager writeBufferManager);
/**
* Reference to {@link WriteBufferManager} used by it.
*
* Default: null (Disabled)
*
* @return a reference to WriteBufferManager
*/
WriteBufferManager writeBufferManager();
/**
* Amount of data to build up in memtables across all column
* families before writing to disk.
*
* This is distinct from {@link ColumnFamilyOptions#writeBufferSize()},
* which enforces a limit for a single memtable.
*
* This feature is disabled by default. Specify a non-zero value
* to enable it.
*
* Default: 0 (disabled)
*
* @return the size of the write buffer
*/
long dbWriteBufferSize();
/**
* Specify the file access pattern once a compaction is started.
* It will be applied to all input files of a compaction.
*
* Default: {@link AccessHint#NORMAL}
*
* @param accessHint The access hint
*
* @return the reference to the current options.
*/
T setAccessHintOnCompactionStart(final AccessHint accessHint);
/**
* Specify the file access pattern once a compaction is started.
* It will be applied to all input files of a compaction.
*
* Default: {@link AccessHint#NORMAL}
*
* @return The access hint
*/
AccessHint accessHintOnCompactionStart();
/**
* If true, always create a new file descriptor and new table reader
* for compaction inputs. Turn this parameter on may introduce extra
* memory usage in the table reader, if it allocates extra memory
* for indexes. This will allow file descriptor prefetch options
* to be set for compaction input files and not to impact file
* descriptors for the same file used by user queries.
* Suggest to enable {@link BlockBasedTableConfig#cacheIndexAndFilterBlocks()}
* for this mode if using block-based table.
*
* Default: false
*
* @param newTableReaderForCompactionInputs true if a new file descriptor and
* table reader should be created for compaction inputs
*
* @return the reference to the current options.
*/
T setNewTableReaderForCompactionInputs(
boolean newTableReaderForCompactionInputs);
/**
* If true, always create a new file descriptor and new table reader
* for compaction inputs. Turn this parameter on may introduce extra
* memory usage in the table reader, if it allocates extra memory
* for indexes. This will allow file descriptor prefetch options
* to be set for compaction input files and not to impact file
* descriptors for the same file used by user queries.
* Suggest to enable {@link BlockBasedTableConfig#cacheIndexAndFilterBlocks()}
* for this mode if using block-based table.
*
* Default: false
*
* @return true if a new file descriptor and table reader are created for
* compaction inputs
*/
boolean newTableReaderForCompactionInputs();
/**
* This is a maximum buffer size that is used by WinMmapReadableFile in
* unbuffered disk I/O mode. We need to maintain an aligned buffer for
* reads. We allow the buffer to grow until the specified value and then
* for bigger requests allocate one shot buffers. In unbuffered mode we
* always bypass read-ahead buffer at ReadaheadRandomAccessFile
* When read-ahead is required we then make use of
* {@link MutableDBOptionsInterface#compactionReadaheadSize()} value and
* always try to read ahead.
* With read-ahead we always pre-allocate buffer to the size instead of
* growing it up to a limit.
*
* This option is currently honored only on Windows
*
* Default: 1 Mb
*
* Special value: 0 - means do not maintain per instance buffer. Allocate
* per request buffer and avoid locking.
*
* @param randomAccessMaxBufferSize the maximum size of the random access
* buffer
*
* @return the reference to the current options.
*/
T setRandomAccessMaxBufferSize(long randomAccessMaxBufferSize);
/**
* This is a maximum buffer size that is used by WinMmapReadableFile in
* unbuffered disk I/O mode. We need to maintain an aligned buffer for
* reads. We allow the buffer to grow until the specified value and then
* for bigger requests allocate one shot buffers. In unbuffered mode we
* always bypass read-ahead buffer at ReadaheadRandomAccessFile
* When read-ahead is required we then make use of
* {@link MutableDBOptionsInterface#compactionReadaheadSize()} value and
* always try to read ahead. With read-ahead we always pre-allocate buffer
* to the size instead of growing it up to a limit.
*
* This option is currently honored only on Windows
*
* Default: 1 Mb
*
* Special value: 0 - means do not maintain per instance buffer. Allocate
* per request buffer and avoid locking.
*
* @return the maximum size of the random access buffer
*/
long randomAccessMaxBufferSize();
/**
* Use adaptive mutex, which spins in the user space before resorting
* to kernel. This could reduce context switch when the mutex is not
* heavily contended. However, if the mutex is hot, we could end up
* wasting spin time.
* Default: false
*
* @param useAdaptiveMutex true if adaptive mutex is used.
* @return the instance of the current object.
*/
T setUseAdaptiveMutex(boolean useAdaptiveMutex);
/**
* Use adaptive mutex, which spins in the user space before resorting
* to kernel. This could reduce context switch when the mutex is not
* heavily contended. However, if the mutex is hot, we could end up
* wasting spin time.
* Default: false
*
* @return true if adaptive mutex is used.
*/
boolean useAdaptiveMutex();
/**
* Sets the {@link EventListener}s whose callback functions
* will be called when specific RocksDB event happens.
*
* Note: the RocksJava API currently only supports EventListeners implemented in Java.
* It could be extended in future to also support adding/removing EventListeners implemented in
* C++.
*
* @param listeners the listeners who should be notified on various events.
*
* @return the instance of the current object.
*/
T setListeners(final List listeners);
/**
* Sets the {@link EventListener}s whose callback functions
* will be called when specific RocksDB event happens.
*
* Note: the RocksJava API currently only supports EventListeners implemented in Java.
* It could be extended in future to also support adding/removing EventListeners implemented in
* C++.
*
* @return the instance of the current object.
*/
List listeners();
/**
* If true, then the status of the threads involved in this DB will
* be tracked and available via GetThreadList() API.
*
* Default: false
*
* @param enableThreadTracking true to enable tracking
*
* @return the reference to the current options.
*/
T setEnableThreadTracking(boolean enableThreadTracking);
/**
* If true, then the status of the threads involved in this DB will
* be tracked and available via GetThreadList() API.
*
* Default: false
*
* @return true if tracking is enabled
*/
boolean enableThreadTracking();
/**
* By default, a single write thread queue is maintained. The thread gets
* to the head of the queue becomes write batch group leader and responsible
* for writing to WAL and memtable for the batch group.
*
* If {@link #enablePipelinedWrite()} is true, separate write thread queue is
* maintained for WAL write and memtable write. A write thread first enter WAL
* writer queue and then memtable writer queue. Pending thread on the WAL
* writer queue thus only have to wait for previous writers to finish their
* WAL writing but not the memtable writing. Enabling the feature may improve
* write throughput and reduce latency of the prepare phase of two-phase
* commit.
*
* Default: false
*
* @param enablePipelinedWrite true to enabled pipelined writes
*
* @return the reference to the current options.
*/
T setEnablePipelinedWrite(final boolean enablePipelinedWrite);
/**
* Returns true if pipelined writes are enabled.
* See {@link #setEnablePipelinedWrite(boolean)}.
*
* @return true if pipelined writes are enabled, false otherwise.
*/
boolean enablePipelinedWrite();
/**
* Setting {@link #unorderedWrite()} to true trades higher write throughput with
* relaxing the immutability guarantee of snapshots. This violates the
* repeatability one expects from ::Get from a snapshot, as well as
* ::MultiGet and Iterator's consistent-point-in-time view property.
* If the application cannot tolerate the relaxed guarantees, it can implement
* its own mechanisms to work around that and yet benefit from the higher
* throughput. Using TransactionDB with WRITE_PREPARED write policy and
* {@link #twoWriteQueues()} true is one way to achieve immutable snapshots despite
* unordered_write.
*
* By default, i.e., when it is false, rocksdb does not advance the sequence
* number for new snapshots unless all the writes with lower sequence numbers
* are already finished. This provides the immutability that we except from
* snapshots. Moreover, since Iterator and MultiGet internally depend on
* snapshots, the snapshot immutability results into Iterator and MultiGet
* offering consistent-point-in-time view. If set to true, although
* Read-Your-Own-Write property is still provided, the snapshot immutability
* property is relaxed: the writes issued after the snapshot is obtained (with
* larger sequence numbers) will be still not visible to the reads from that
* snapshot, however, there still might be pending writes (with lower sequence
* number) that will change the state visible to the snapshot after they are
* landed to the memtable.
*
* @param unorderedWrite true to enabled unordered write
*
* @return the reference to the current options.
*/
T setUnorderedWrite(final boolean unorderedWrite);
/**
* Returns true if unordered write are enabled.
* See {@link #setUnorderedWrite(boolean)}.
*
* @return true if unordered write are enabled, false otherwise.
*/
boolean unorderedWrite();
/**
* If true, allow multi-writers to update mem tables in parallel.
* Only some memtable factorys support concurrent writes; currently it
* is implemented only for SkipListFactory. Concurrent memtable writes
* are not compatible with inplace_update_support or filter_deletes.
* It is strongly recommended to set
* {@link #setEnableWriteThreadAdaptiveYield(boolean)} if you are going to use
* this feature.
* Default: true
*
* @param allowConcurrentMemtableWrite true to enable concurrent writes
* for the memtable
*
* @return the reference to the current options.
*/
T setAllowConcurrentMemtableWrite(boolean allowConcurrentMemtableWrite);
/**
* If true, allow multi-writers to update mem tables in parallel.
* Only some memtable factorys support concurrent writes; currently it
* is implemented only for SkipListFactory. Concurrent memtable writes
* are not compatible with inplace_update_support or filter_deletes.
* It is strongly recommended to set
* {@link #setEnableWriteThreadAdaptiveYield(boolean)} if you are going to use
* this feature.
* Default: true
*
* @return true if concurrent writes are enabled for the memtable
*/
boolean allowConcurrentMemtableWrite();
/**
* If true, threads synchronizing with the write batch group leader will
* wait for up to {@link #writeThreadMaxYieldUsec()} before blocking on a
* mutex. This can substantially improve throughput for concurrent workloads,
* regardless of whether {@link #allowConcurrentMemtableWrite()} is enabled.
* Default: true
*
* @param enableWriteThreadAdaptiveYield true to enable adaptive yield for the
* write threads
*
* @return the reference to the current options.
*/
T setEnableWriteThreadAdaptiveYield(
boolean enableWriteThreadAdaptiveYield);
/**
* If true, threads synchronizing with the write batch group leader will
* wait for up to {@link #writeThreadMaxYieldUsec()} before blocking on a
* mutex. This can substantially improve throughput for concurrent workloads,
* regardless of whether {@link #allowConcurrentMemtableWrite()} is enabled.
* Default: true
*
* @return true if adaptive yield is enabled
* for the writing threads
*/
boolean enableWriteThreadAdaptiveYield();
/**
* The maximum number of microseconds that a write operation will use
* a yielding spin loop to coordinate with other write threads before
* blocking on a mutex. (Assuming {@link #writeThreadSlowYieldUsec()} is
* set properly) increasing this value is likely to increase RocksDB
* throughput at the expense of increased CPU usage.
* Default: 100
*
* @param writeThreadMaxYieldUsec maximum number of microseconds
*
* @return the reference to the current options.
*/
T setWriteThreadMaxYieldUsec(long writeThreadMaxYieldUsec);
/**
* The maximum number of microseconds that a write operation will use
* a yielding spin loop to coordinate with other write threads before
* blocking on a mutex. (Assuming {@link #writeThreadSlowYieldUsec()} is
* set properly) increasing this value is likely to increase RocksDB
* throughput at the expense of increased CPU usage.
* Default: 100
*
* @return the maximum number of microseconds
*/
long writeThreadMaxYieldUsec();
/**
* The latency in microseconds after which a std::this_thread::yield
* call (sched_yield on Linux) is considered to be a signal that
* other processes or threads would like to use the current core.
* Increasing this makes writer threads more likely to take CPU
* by spinning, which will show up as an increase in the number of
* involuntary context switches.
* Default: 3
*
* @param writeThreadSlowYieldUsec the latency in microseconds
*
* @return the reference to the current options.
*/
T setWriteThreadSlowYieldUsec(long writeThreadSlowYieldUsec);
/**
* The latency in microseconds after which a std::this_thread::yield
* call (sched_yield on Linux) is considered to be a signal that
* other processes or threads would like to use the current core.
* Increasing this makes writer threads more likely to take CPU
* by spinning, which will show up as an increase in the number of
* involuntary context switches.
* Default: 3
*
* @return writeThreadSlowYieldUsec the latency in microseconds
*/
long writeThreadSlowYieldUsec();
/**
* If true, then DB::Open() will not update the statistics used to optimize
* compaction decision by loading table properties from many files.
* Turning off this feature will improve DBOpen time especially in
* disk environment.
*
* Default: false
*
* @param skipStatsUpdateOnDbOpen true if updating stats will be skipped
*
* @return the reference to the current options.
*/
T setSkipStatsUpdateOnDbOpen(boolean skipStatsUpdateOnDbOpen);
/**
* If true, then DB::Open() will not update the statistics used to optimize
* compaction decision by loading table properties from many files.
* Turning off this feature will improve DBOpen time especially in
* disk environment.
*
* Default: false
*
* @return true if updating stats will be skipped
*/
boolean skipStatsUpdateOnDbOpen();
/**
* If true, then {@link RocksDB#open(String)} will not fetch and check sizes of all sst files.
* This may significantly speed up startup if there are many sst files,
* especially when using non-default Env with expensive GetFileSize().
* We'll still check that all required sst files exist.
* If {@code paranoid_checks} is false, this option is ignored, and sst files are
* not checked at all.
*
* Default: false
*
* @param skipCheckingSstFileSizesOnDbOpen if true, then SST file sizes will not be checked
* when calling {@link RocksDB#open(String)}.
* @return the reference to the current options.
*/
T setSkipCheckingSstFileSizesOnDbOpen(final boolean skipCheckingSstFileSizesOnDbOpen);
/**
* If true, then {@link RocksDB#open(String)} will not fetch and check sizes of all sst files.
* This may significantly speed up startup if there are many sst files,
* especially when using non-default Env with expensive GetFileSize().
* We'll still check that all required sst files exist.
* If {@code paranoid_checks} is false, this option is ignored, and sst files are
* not checked at all.
*
* Default: false
*
* @return true, if file sizes will not be checked when calling {@link RocksDB#open(String)}.
*/
boolean skipCheckingSstFileSizesOnDbOpen();
/**
* Recovery mode to control the consistency while replaying WAL
*
* Default: {@link WALRecoveryMode#PointInTimeRecovery}
*
* @param walRecoveryMode The WAL recover mode
*
* @return the reference to the current options.
*/
T setWalRecoveryMode(WALRecoveryMode walRecoveryMode);
/**
* Recovery mode to control the consistency while replaying WAL
*
* Default: {@link WALRecoveryMode#PointInTimeRecovery}
*
* @return The WAL recover mode
*/
WALRecoveryMode walRecoveryMode();
/**
* if set to false then recovery will fail when a prepared
* transaction is encountered in the WAL
*
* Default: false
*
* @param allow2pc true if two-phase-commit is enabled
*
* @return the reference to the current options.
*/
T setAllow2pc(boolean allow2pc);
/**
* if set to false then recovery will fail when a prepared
* transaction is encountered in the WAL
*
* Default: false
*
* @return true if two-phase-commit is enabled
*/
boolean allow2pc();
/**
* A global cache for table-level rows.
*
* Default: null (disabled)
*
* @param rowCache The global row cache
*
* @return the reference to the current options.
*/
T setRowCache(final Cache rowCache);
/**
* A global cache for table-level rows.
*
* Default: null (disabled)
*
* @return The global row cache
*/
Cache rowCache();
/**
* A filter object supplied to be invoked while processing write-ahead-logs
* (WALs) during recovery. The filter provides a way to inspect log
* records, ignoring a particular record or skipping replay.
* The filter is invoked at startup and is invoked from a single-thread
* currently.
*
* @param walFilter the filter for processing WALs during recovery.
*
* @return the reference to the current options.
*/
T setWalFilter(final AbstractWalFilter walFilter);
/**
* Get's the filter for processing WALs during recovery.
* See {@link #setWalFilter(AbstractWalFilter)}.
*
* @return the filter used for processing WALs during recovery.
*/
WalFilter walFilter();
/**
* If true, then DB::Open / CreateColumnFamily / DropColumnFamily
* / SetOptions will fail if options file is not detected or properly
* persisted.
*
* DEFAULT: false
*
* @param failIfOptionsFileError true if we should fail if there is an error
* in the options file
*
* @return the reference to the current options.
*/
T setFailIfOptionsFileError(boolean failIfOptionsFileError);
/**
* If true, then DB::Open / CreateColumnFamily / DropColumnFamily
* / SetOptions will fail if options file is not detected or properly
* persisted.
*
* DEFAULT: false
*
* @return true if we should fail if there is an error in the options file
*/
boolean failIfOptionsFileError();
/**
* If true, then print malloc stats together with rocksdb.stats
* when printing to LOG.
*
* DEFAULT: false
*
* @param dumpMallocStats true if malloc stats should be printed to LOG
*
* @return the reference to the current options.
*/
T setDumpMallocStats(boolean dumpMallocStats);
/**
* If true, then print malloc stats together with rocksdb.stats
* when printing to LOG.
*
* DEFAULT: false
*
* @return true if malloc stats should be printed to LOG
*/
boolean dumpMallocStats();
/**
* By default RocksDB replay WAL logs and flush them on DB open, which may
* create very small SST files. If this option is enabled, RocksDB will try
* to avoid (but not guarantee not to) flush during recovery. Also, existing
* WAL logs will be kept, so that if crash happened before flush, we still
* have logs to recover from.
*
* DEFAULT: false
*
* @param avoidFlushDuringRecovery true to try to avoid (but not guarantee
* not to) flush during recovery
*
* @return the reference to the current options.
*/
T setAvoidFlushDuringRecovery(boolean avoidFlushDuringRecovery);
/**
* By default RocksDB replay WAL logs and flush them on DB open, which may
* create very small SST files. If this option is enabled, RocksDB will try
* to avoid (but not guarantee not to) flush during recovery. Also, existing
* WAL logs will be kept, so that if crash happened before flush, we still
* have logs to recover from.
*
* DEFAULT: false
*
* @return true to try to avoid (but not guarantee not to) flush during
* recovery
*/
boolean avoidFlushDuringRecovery();
/**
* Set this option to true during creation of database if you want
* to be able to ingest behind (call IngestExternalFile() skipping keys
* that already exist, rather than overwriting matching keys).
* Setting this option to true will affect 2 things:
* 1) Disable some internal optimizations around SST file compression
* 2) Reserve bottom-most level for ingested files only.
* 3) Note that num_levels should be >= 3 if this option is turned on.
*
* DEFAULT: false
*
* @param allowIngestBehind true to allow ingest behind, false to disallow.
*
* @return the reference to the current options.
*/
T setAllowIngestBehind(final boolean allowIngestBehind);
/**
* Returns true if ingest behind is allowed.
* See {@link #setAllowIngestBehind(boolean)}.
*
* @return true if ingest behind is allowed, false otherwise.
*/
boolean allowIngestBehind();
/**
* Needed to support differential snapshots.
* If set to true then DB will only process deletes with sequence number
* less than what was set by SetPreserveDeletesSequenceNumber(uint64_t ts).
* Clients are responsible to periodically call this method to advance
* the cutoff time. If this method is never called and preserve_deletes
* is set to true NO deletes will ever be processed.
* At the moment this only keeps normal deletes, SingleDeletes will
* not be preserved.
*
* DEFAULT: false
*
* @param preserveDeletes true to preserve deletes.
*
* @return the reference to the current options.
*/
T setPreserveDeletes(final boolean preserveDeletes);
/**
* Returns true if deletes are preserved.
* See {@link #setPreserveDeletes(boolean)}.
*
* @return true if deletes are preserved, false otherwise.
*/
boolean preserveDeletes();
/**
* If enabled it uses two queues for writes, one for the ones with
* disable_memtable and one for the ones that also write to memtable. This
* allows the memtable writes not to lag behind other writes. It can be used
* to optimize MySQL 2PC in which only the commits, which are serial, write to
* memtable.
*
* DEFAULT: false
*
* @param twoWriteQueues true to enable two write queues, false otherwise.
*
* @return the reference to the current options.
*/
T setTwoWriteQueues(final boolean twoWriteQueues);
/**
* Returns true if two write queues are enabled.
*
* @return true if two write queues are enabled, false otherwise.
*/
boolean twoWriteQueues();
/**
* If true WAL is not flushed automatically after each write. Instead it
* relies on manual invocation of FlushWAL to write the WAL buffer to its
* file.
*
* DEFAULT: false
*
* @param manualWalFlush true to set disable automatic WAL flushing,
* false otherwise.
*
* @return the reference to the current options.
*/
T setManualWalFlush(final boolean manualWalFlush);
/**
* Returns true if automatic WAL flushing is disabled.
* See {@link #setManualWalFlush(boolean)}.
*
* @return true if automatic WAL flushing is disabled, false otherwise.
*/
boolean manualWalFlush();
/**
* If true, RocksDB supports flushing multiple column families and committing
* their results atomically to MANIFEST. Note that it is not
* necessary to set atomic_flush to true if WAL is always enabled since WAL
* allows the database to be restored to the last persistent state in WAL.
* This option is useful when there are column families with writes NOT
* protected by WAL.
* For manual flush, application has to specify which column families to
* flush atomically in {@link RocksDB#flush(FlushOptions, List)}.
* For auto-triggered flush, RocksDB atomically flushes ALL column families.
*
* Currently, any WAL-enabled writes after atomic flush may be replayed
* independently if the process crashes later and tries to recover.
*
* @param atomicFlush true to enable atomic flush of multiple column families.
*
* @return the reference to the current options.
*/
T setAtomicFlush(final boolean atomicFlush);
/**
* Determine if atomic flush of multiple column families is enabled.
*
* See {@link #setAtomicFlush(boolean)}.
*
* @return true if atomic flush is enabled.
*/
boolean atomicFlush();
/**
* If true, working thread may avoid doing unnecessary and long-latency
* operation (such as deleting obsolete files directly or deleting memtable)
* and will instead schedule a background job to do it.
* Use it if you're latency-sensitive.
* If set to true, takes precedence over
* {@link ReadOptions#setBackgroundPurgeOnIteratorCleanup(boolean)}.
*
* @param avoidUnnecessaryBlockingIO If true, working thread may avoid doing unnecessary
* operation.
* @return the reference to the current options.
*/
T setAvoidUnnecessaryBlockingIO(final boolean avoidUnnecessaryBlockingIO);
/**
* If true, working thread may avoid doing unnecessary and long-latency
* operation (such as deleting obsolete files directly or deleting memtable)
* and will instead schedule a background job to do it.
* Use it if you're latency-sensitive.
* If set to true, takes precedence over
* {@link ReadOptions#setBackgroundPurgeOnIteratorCleanup(boolean)}.
*
* @return true, if working thread may avoid doing unnecessary operation.
*/
boolean avoidUnnecessaryBlockingIO();
/**
* If true, automatically persist stats to a hidden column family (column
* family name: ___rocksdb_stats_history___) every
* stats_persist_period_sec seconds; otherwise, write to an in-memory
* struct. User can query through `GetStatsHistory` API.
* If user attempts to create a column family with the same name on a DB
* which have previously set persist_stats_to_disk to true, the column family
* creation will fail, but the hidden column family will survive, as well as
* the previously persisted statistics.
* When peristing stats to disk, the stat name will be limited at 100 bytes.
* Default: false
*
* @param persistStatsToDisk true if stats should be persisted to hidden column family.
* @return the instance of the current object.
*/
T setPersistStatsToDisk(final boolean persistStatsToDisk);
/**
* If true, automatically persist stats to a hidden column family (column
* family name: ___rocksdb_stats_history___) every
* stats_persist_period_sec seconds; otherwise, write to an in-memory
* struct. User can query through `GetStatsHistory` API.
* If user attempts to create a column family with the same name on a DB
* which have previously set persist_stats_to_disk to true, the column family
* creation will fail, but the hidden column family will survive, as well as
* the previously persisted statistics.
* When peristing stats to disk, the stat name will be limited at 100 bytes.
* Default: false
*
* @return true if stats should be persisted to hidden column family.
*/
boolean persistStatsToDisk();
/**
* Historically DB ID has always been stored in Identity File in DB folder.
* If this flag is true, the DB ID is written to Manifest file in addition
* to the Identity file. By doing this 2 problems are solved
* 1. We don't checksum the Identity file where as Manifest file is.
* 2. Since the source of truth for DB is Manifest file DB ID will sit with
* the source of truth. Previously the Identity file could be copied
* independent of Manifest and that can result in wrong DB ID.
* We recommend setting this flag to true.
* Default: false
*
* @param writeDbidToManifest if true, then DB ID will be written to Manifest file.
* @return the instance of the current object.
*/
T setWriteDbidToManifest(final boolean writeDbidToManifest);
/**
* Historically DB ID has always been stored in Identity File in DB folder.
* If this flag is true, the DB ID is written to Manifest file in addition
* to the Identity file. By doing this 2 problems are solved
* 1. We don't checksum the Identity file where as Manifest file is.
* 2. Since the source of truth for DB is Manifest file DB ID will sit with
* the source of truth. Previously the Identity file could be copied
* independent of Manifest and that can result in wrong DB ID.
* We recommend setting this flag to true.
* Default: false
*
* @return true, if DB ID will be written to Manifest file.
*/
boolean writeDbidToManifest();
/**
* The number of bytes to prefetch when reading the log. This is mostly useful
* for reading a remotely located log, as it can save the number of
* round-trips. If 0, then the prefetching is disabled.
*
* Default: 0
*
* @param logReadaheadSize the number of bytes to prefetch when reading the log.
* @return the instance of the current object.
*/
T setLogReadaheadSize(final long logReadaheadSize);
/**
* The number of bytes to prefetch when reading the log. This is mostly useful
* for reading a remotely located log, as it can save the number of
* round-trips. If 0, then the prefetching is disabled.
*
* Default: 0
*
* @return the number of bytes to prefetch when reading the log.
*/
long logReadaheadSize();
/**
* By default, RocksDB recovery fails if any table file referenced in
* MANIFEST are missing after scanning the MANIFEST.
* Best-efforts recovery is another recovery mode that
* tries to restore the database to the most recent point in time without
* missing file.
* Currently not compatible with atomic flush. Furthermore, WAL files will
* not be used for recovery if best_efforts_recovery is true.
* Default: false
*
* @param bestEffortsRecovery if true, RocksDB will use best-efforts mode when recovering.
* @return the instance of the current object.
*/
T setBestEffortsRecovery(final boolean bestEffortsRecovery);
/**
* By default, RocksDB recovery fails if any table file referenced in
* MANIFEST are missing after scanning the MANIFEST.
* Best-efforts recovery is another recovery mode that
* tries to restore the database to the most recent point in time without
* missing file.
* Currently not compatible with atomic flush. Furthermore, WAL files will
* not be used for recovery if best_efforts_recovery is true.
* Default: false
*
* @return true, if RocksDB uses best-efforts mode when recovering.
*/
boolean bestEffortsRecovery();
/**
* It defines how many times db resume is called by a separate thread when
* background retryable IO Error happens. When background retryable IO
* Error happens, SetBGError is called to deal with the error. If the error
* can be auto-recovered (e.g., retryable IO Error during Flush or WAL write),
* then db resume is called in background to recover from the error. If this
* value is 0 or negative, db resume will not be called.
*
* Default: INT_MAX
*
* @param maxBgerrorResumeCount maximum number of times db resume should be called when IO Error
* happens.
* @return the instance of the current object.
*/
T setMaxBgErrorResumeCount(final int maxBgerrorResumeCount);
/**
* It defines how many times db resume is called by a separate thread when
* background retryable IO Error happens. When background retryable IO
* Error happens, SetBGError is called to deal with the error. If the error
* can be auto-recovered (e.g., retryable IO Error during Flush or WAL write),
* then db resume is called in background to recover from the error. If this
* value is 0 or negative, db resume will not be called.
*
* Default: INT_MAX
*
* @return maximum number of times db resume should be called when IO Error happens.
*/
int maxBgerrorResumeCount();
/**
* If max_bgerror_resume_count is ≥ 2, db resume is called multiple times.
* This option decides how long to wait to retry the next resume if the
* previous resume fails and satisfy redo resume conditions.
*
* Default: 1000000 (microseconds).
*
* @param bgerrorResumeRetryInterval how many microseconds to wait between DB resume attempts.
* @return the instance of the current object.
*/
T setBgerrorResumeRetryInterval(final long bgerrorResumeRetryInterval);
/**
* If max_bgerror_resume_count is ≥ 2, db resume is called multiple times.
* This option decides how long to wait to retry the next resume if the
* previous resume fails and satisfy redo resume conditions.
*
* Default: 1000000 (microseconds).
*
* @return the instance of the current object.
*/
long bgerrorResumeRetryInterval();
}