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// 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.forstdb;
/**
* Advanced Column Family Options which are mutable
*
* Taken from include/rocksdb/advanced_options.h
* and MutableCFOptions in util/cf_options.h
*/
public interface AdvancedMutableColumnFamilyOptionsInterface<
T extends AdvancedMutableColumnFamilyOptionsInterface> {
/**
* The maximum number of write buffers that are built up in memory.
* The default is 2, so that when 1 write buffer is being flushed to
* storage, new writes can continue to the other write buffer.
* Default: 2
*
* @param maxWriteBufferNumber maximum number of write buffers.
* @return the instance of the current options.
*/
T setMaxWriteBufferNumber(
int maxWriteBufferNumber);
/**
* Returns maximum number of write buffers.
*
* @return maximum number of write buffers.
* @see #setMaxWriteBufferNumber(int)
*/
int maxWriteBufferNumber();
/**
* Number of locks used for inplace update
* Default: 10000, if inplace_update_support = true, else 0.
*
* @param inplaceUpdateNumLocks the number of locks used for
* inplace updates.
* @return the reference to the current options.
* @throws java.lang.IllegalArgumentException thrown on 32-Bit platforms
* while overflowing the underlying platform specific value.
*/
T setInplaceUpdateNumLocks(
long inplaceUpdateNumLocks);
/**
* Number of locks used for inplace update
* Default: 10000, if inplace_update_support = true, else 0.
*
* @return the number of locks used for inplace update.
*/
long inplaceUpdateNumLocks();
/**
* if prefix_extractor is set and memtable_prefix_bloom_size_ratio is not 0,
* create prefix bloom for memtable with the size of
* write_buffer_size * memtable_prefix_bloom_size_ratio.
* If it is larger than 0.25, it is sanitized to 0.25.
*
* Default: 0 (disabled)
*
* @param memtablePrefixBloomSizeRatio the ratio of memtable used by the
* bloom filter, 0 means no bloom filter
* @return the reference to the current options.
*/
T setMemtablePrefixBloomSizeRatio(
double memtablePrefixBloomSizeRatio);
/**
* if prefix_extractor is set and memtable_prefix_bloom_size_ratio is not 0,
* create prefix bloom for memtable with the size of
* write_buffer_size * memtable_prefix_bloom_size_ratio.
* If it is larger than 0.25, it is sanitized to 0.25.
*
* Default: 0 (disabled)
*
* @return the ratio of memtable used by the bloom filter
*/
double memtablePrefixBloomSizeRatio();
/**
* Threshold used in the MemPurge (memtable garbage collection)
* feature. A value of 0.0 corresponds to no MemPurge,
* a value of 1.0 will trigger a MemPurge as often as possible.
*
* Default: 0.0 (disabled)
*
* @param experimentalMempurgeThreshold the threshold used by
* the MemPurge decider.
* @return the reference to the current options.
*/
T setExperimentalMempurgeThreshold(double experimentalMempurgeThreshold);
/**
* Threshold used in the MemPurge (memtable garbage collection)
* feature. A value of 0.0 corresponds to no MemPurge,
* a value of 1.0 will trigger a MemPurge as often as possible.
*
* Default: 0 (disabled)
*
* @return the threshold used by the MemPurge decider
*/
double experimentalMempurgeThreshold();
/**
* Enable whole key bloom filter in memtable. Note this will only take effect
* if memtable_prefix_bloom_size_ratio is not 0. Enabling whole key filtering
* can potentially reduce CPU usage for point-look-ups.
*
* Default: false (disabled)
*
* @param memtableWholeKeyFiltering true if whole key bloom filter is enabled
* in memtable
* @return the reference to the current options.
*/
T setMemtableWholeKeyFiltering(boolean memtableWholeKeyFiltering);
/**
* Returns whether whole key bloom filter is enabled in memtable
*
* @return true if whole key bloom filter is enabled in memtable
*/
boolean memtableWholeKeyFiltering();
/**
* Page size for huge page TLB for bloom in memtable. If ≤ 0, not allocate
* from huge page TLB but from malloc.
* Need to reserve huge pages for it to be allocated. For example:
* sysctl -w vm.nr_hugepages=20
* See linux doc Documentation/vm/hugetlbpage.txt
*
* @param memtableHugePageSize The page size of the huge
* page tlb
* @return the reference to the current options.
*/
T setMemtableHugePageSize(
long memtableHugePageSize);
/**
* Page size for huge page TLB for bloom in memtable. If ≤ 0, not allocate
* from huge page TLB but from malloc.
* Need to reserve huge pages for it to be allocated. For example:
* sysctl -w vm.nr_hugepages=20
* See linux doc Documentation/vm/hugetlbpage.txt
*
* @return The page size of the huge page tlb
*/
long memtableHugePageSize();
/**
* The size of one block in arena memory allocation.
* If ≤ 0, a proper value is automatically calculated (usually 1/10 of
* writer_buffer_size).
*
* There are two additional restriction of the specified size:
* (1) size should be in the range of [4096, 2 << 30] and
* (2) be the multiple of the CPU word (which helps with the memory
* alignment).
*
* We'll automatically check and adjust the size number to make sure it
* conforms to the restrictions.
* Default: 0
*
* @param arenaBlockSize the size of an arena block
* @return the reference to the current options.
* @throws java.lang.IllegalArgumentException thrown on 32-Bit platforms
* while overflowing the underlying platform specific value.
*/
T setArenaBlockSize(long arenaBlockSize);
/**
* The size of one block in arena memory allocation.
* If ≤ 0, a proper value is automatically calculated (usually 1/10 of
* writer_buffer_size).
*
* There are two additional restriction of the specified size:
* (1) size should be in the range of [4096, 2 << 30] and
* (2) be the multiple of the CPU word (which helps with the memory
* alignment).
*
* We'll automatically check and adjust the size number to make sure it
* conforms to the restrictions.
* Default: 0
*
* @return the size of an arena block
*/
long arenaBlockSize();
/**
* Soft limit on number of level-0 files. We start slowing down writes at this
* point. A value < 0 means that no writing slow down will be triggered by
* number of files in level-0.
*
* @param level0SlowdownWritesTrigger The soft limit on the number of
* level-0 files
* @return the reference to the current options.
*/
T setLevel0SlowdownWritesTrigger(
int level0SlowdownWritesTrigger);
/**
* Soft limit on number of level-0 files. We start slowing down writes at this
* point. A value < 0 means that no writing slow down will be triggered by
* number of files in level-0.
*
* @return The soft limit on the number of
* level-0 files
*/
int level0SlowdownWritesTrigger();
/**
* Maximum number of level-0 files. We stop writes at this point.
*
* @param level0StopWritesTrigger The maximum number of level-0 files
* @return the reference to the current options.
*/
T setLevel0StopWritesTrigger(
int level0StopWritesTrigger);
/**
* Maximum number of level-0 files. We stop writes at this point.
*
* @return The maximum number of level-0 files
*/
int level0StopWritesTrigger();
/**
* The target file size for compaction.
* This targetFileSizeBase determines a level-1 file size.
* Target file size for level L can be calculated by
* targetFileSizeBase * (targetFileSizeMultiplier ^ (L-1))
* For example, if targetFileSizeBase is 2MB and
* target_file_size_multiplier is 10, then each file on level-1 will
* be 2MB, and each file on level 2 will be 20MB,
* and each file on level-3 will be 200MB.
* by default targetFileSizeBase is 64MB.
*
* @param targetFileSizeBase the target size of a level-0 file.
* @return the reference to the current options.
*
* @see #setTargetFileSizeMultiplier(int)
*/
T setTargetFileSizeBase(
long targetFileSizeBase);
/**
* The target file size for compaction.
* This targetFileSizeBase determines a level-1 file size.
* Target file size for level L can be calculated by
* targetFileSizeBase * (targetFileSizeMultiplier ^ (L-1))
* For example, if targetFileSizeBase is 2MB and
* target_file_size_multiplier is 10, then each file on level-1 will
* be 2MB, and each file on level 2 will be 20MB,
* and each file on level-3 will be 200MB.
* by default targetFileSizeBase is 64MB.
*
* @return the target size of a level-0 file.
*
* @see #targetFileSizeMultiplier()
*/
long targetFileSizeBase();
/**
* targetFileSizeMultiplier defines the size ratio between a
* level-L file and level-(L+1) file.
* By default target_file_size_multiplier is 1, meaning
* files in different levels have the same target.
*
* @param multiplier the size ratio between a level-(L+1) file
* and level-L file.
* @return the reference to the current options.
*/
T setTargetFileSizeMultiplier(
int multiplier);
/**
* targetFileSizeMultiplier defines the size ratio between a
* level-(L+1) file and level-L file.
* By default targetFileSizeMultiplier is 1, meaning
* files in different levels have the same target.
*
* @return the size ratio between a level-(L+1) file and level-L file.
*/
int targetFileSizeMultiplier();
/**
* The ratio between the total size of level-(L+1) files and the total
* size of level-L files for all L.
* DEFAULT: 10
*
* @param multiplier the ratio between the total size of level-(L+1)
* files and the total size of level-L files for all L.
* @return the reference to the current options.
*
* See {@link MutableColumnFamilyOptionsInterface#setMaxBytesForLevelBase(long)}
*/
T setMaxBytesForLevelMultiplier(double multiplier);
/**
* The ratio between the total size of level-(L+1) files and the total
* size of level-L files for all L.
* DEFAULT: 10
*
* @return the ratio between the total size of level-(L+1) files and
* the total size of level-L files for all L.
*
* See {@link MutableColumnFamilyOptionsInterface#maxBytesForLevelBase()}
*/
double maxBytesForLevelMultiplier();
/**
* Different max-size multipliers for different levels.
* These are multiplied by max_bytes_for_level_multiplier to arrive
* at the max-size of each level.
*
* Default: 1
*
* @param maxBytesForLevelMultiplierAdditional The max-size multipliers
* for each level
* @return the reference to the current options.
*/
T setMaxBytesForLevelMultiplierAdditional(
int[] maxBytesForLevelMultiplierAdditional);
/**
* Different max-size multipliers for different levels.
* These are multiplied by max_bytes_for_level_multiplier to arrive
* at the max-size of each level.
*
* Default: 1
*
* @return The max-size multipliers for each level
*/
int[] maxBytesForLevelMultiplierAdditional();
/**
* All writes will be slowed down to at least delayed_write_rate if estimated
* bytes needed to be compaction exceed this threshold.
*
* Default: 64GB
*
* @param softPendingCompactionBytesLimit The soft limit to impose on
* compaction
* @return the reference to the current options.
*/
T setSoftPendingCompactionBytesLimit(
long softPendingCompactionBytesLimit);
/**
* All writes will be slowed down to at least delayed_write_rate if estimated
* bytes needed to be compaction exceed this threshold.
*
* Default: 64GB
*
* @return The soft limit to impose on compaction
*/
long softPendingCompactionBytesLimit();
/**
* All writes are stopped if estimated bytes needed to be compaction exceed
* this threshold.
*
* Default: 256GB
*
* @param hardPendingCompactionBytesLimit The hard limit to impose on
* compaction
* @return the reference to the current options.
*/
T setHardPendingCompactionBytesLimit(
long hardPendingCompactionBytesLimit);
/**
* All writes are stopped if estimated bytes needed to be compaction exceed
* this threshold.
*
* Default: 256GB
*
* @return The hard limit to impose on compaction
*/
long hardPendingCompactionBytesLimit();
/**
* An iteration->Next() sequentially skips over keys with the same
* user-key unless this option is set. This number specifies the number
* of keys (with the same userkey) that will be sequentially
* skipped before a reseek is issued.
* Default: 8
*
* @param maxSequentialSkipInIterations the number of keys could
* be skipped in an iteration.
* @return the reference to the current options.
*/
T setMaxSequentialSkipInIterations(
long maxSequentialSkipInIterations);
/**
* An iteration->Next() sequentially skips over keys with the same
* user-key unless this option is set. This number specifies the number
* of keys (with the same userkey) that will be sequentially
* skipped before a reseek is issued.
* Default: 8
*
* @return the number of keys could be skipped in an iteration.
*/
long maxSequentialSkipInIterations();
/**
* Maximum number of successive merge operations on a key in the memtable.
*
* When a merge operation is added to the memtable and the maximum number of
* successive merges is reached, the value of the key will be calculated and
* inserted into the memtable instead of the merge operation. This will
* ensure that there are never more than max_successive_merges merge
* operations in the memtable.
*
* Default: 0 (disabled)
*
* @param maxSuccessiveMerges the maximum number of successive merges.
* @return the reference to the current options.
* @throws java.lang.IllegalArgumentException thrown on 32-Bit platforms
* while overflowing the underlying platform specific value.
*/
T setMaxSuccessiveMerges(
long maxSuccessiveMerges);
/**
* Maximum number of successive merge operations on a key in the memtable.
*
* When a merge operation is added to the memtable and the maximum number of
* successive merges is reached, the value of the key will be calculated and
* inserted into the memtable instead of the merge operation. This will
* ensure that there are never more than max_successive_merges merge
* operations in the memtable.
*
* Default: 0 (disabled)
*
* @return the maximum number of successive merges.
*/
long maxSuccessiveMerges();
/**
* After writing every SST file, reopen it and read all the keys.
*
* Default: false
*
* @param paranoidFileChecks true to enable paranoid file checks
* @return the reference to the current options.
*/
T setParanoidFileChecks(
boolean paranoidFileChecks);
/**
* After writing every SST file, reopen it and read all the keys.
*
* Default: false
*
* @return true if paranoid file checks are enabled
*/
boolean paranoidFileChecks();
/**
* Measure IO stats in compactions and flushes, if true.
*
* Default: false
*
* @param reportBgIoStats true to enable reporting
* @return the reference to the current options.
*/
T setReportBgIoStats(
boolean reportBgIoStats);
/**
* Determine whether IO stats in compactions and flushes are being measured
*
* @return true if reporting is enabled
*/
boolean reportBgIoStats();
/**
* Non-bottom-level files older than TTL will go through the compaction
* process. This needs {@link MutableDBOptionsInterface#maxOpenFiles()} to be
* set to -1.
*
* Enabled only for level compaction for now.
*
* Default: 0 (disabled)
*
* Dynamically changeable through
* {@link RocksDB#setOptions(ColumnFamilyHandle, MutableColumnFamilyOptions)}.
*
* @param ttl the time-to-live.
*
* @return the reference to the current options.
*/
T setTtl(final long ttl);
/**
* Get the TTL for Non-bottom-level files that will go through the compaction
* process.
*
* See {@link #setTtl(long)}.
*
* @return the time-to-live.
*/
long ttl();
/**
* Files older than this value will be picked up for compaction, and
* re-written to the same level as they were before.
* One main use of the feature is to make sure a file goes through compaction
* filters periodically. Users can also use the feature to clear up SST
* files using old format.
*
* A file's age is computed by looking at file_creation_time or creation_time
* table properties in order, if they have valid non-zero values; if not, the
* age is based on the file's last modified time (given by the underlying
* Env).
*
* Supported in Level and FIFO compaction.
* In FIFO compaction, this option has the same meaning as TTL and whichever
* stricter will be used.
* Pre-req: max_open_file == -1.
* unit: seconds. Ex: 7 days = 7 * 24 * 60 * 60
*
* Values:
* 0: Turn off Periodic compactions.
* UINT64_MAX - 1 (i.e 0xfffffffffffffffe): Let RocksDB control this feature
* as needed. For now, RocksDB will change this value to 30 days
* (i.e 30 * 24 * 60 * 60) so that every file goes through the compaction
* process at least once every 30 days if not compacted sooner.
* In FIFO compaction, since the option has the same meaning as ttl,
* when this value is left default, and ttl is left to 0, 30 days will be
* used. Otherwise, min(ttl, periodic_compaction_seconds) will be used.
*
* Default: 0xfffffffffffffffe (allow RocksDB to auto-tune)
*
* Dynamically changeable through
* {@link RocksDB#setOptions(ColumnFamilyHandle, MutableColumnFamilyOptions)}.
*
* @param periodicCompactionSeconds the periodic compaction in seconds.
*
* @return the reference to the current options.
*/
T setPeriodicCompactionSeconds(final long periodicCompactionSeconds);
/**
* Get the periodicCompactionSeconds.
*
* See {@link #setPeriodicCompactionSeconds(long)}.
*
* @return the periodic compaction in seconds.
*/
long periodicCompactionSeconds();
//
// BEGIN options for blobs (integrated BlobDB)
//
/**
* When set, large values (blobs) are written to separate blob files, and only
* pointers to them are stored in SST files. This can reduce write amplification
* for large-value use cases at the cost of introducing a level of indirection
* for reads. See also the options min_blob_size, blob_file_size,
* blob_compression_type, enable_blob_garbage_collection, and
* blob_garbage_collection_age_cutoff below.
*
* Default: false
*
* Dynamically changeable through
* {@link RocksDB#setOptions(ColumnFamilyHandle, MutableColumnFamilyOptions)}.
*
* @param enableBlobFiles true iff blob files should be enabled
*
* @return the reference to the current options.
*/
T setEnableBlobFiles(final boolean enableBlobFiles);
/**
* When set, large values (blobs) are written to separate blob files, and only
* pointers to them are stored in SST files. This can reduce write amplification
* for large-value use cases at the cost of introducing a level of indirection
* for reads. See also the options min_blob_size, blob_file_size,
* blob_compression_type, enable_blob_garbage_collection, and
* blob_garbage_collection_age_cutoff below.
*
* Default: false
*
* Dynamically changeable through
* {@link RocksDB#setOptions(ColumnFamilyHandle, MutableColumnFamilyOptions)}.
*
* @return true if blob files are enabled
*/
boolean enableBlobFiles();
/**
* Set the size of the smallest value to be stored separately in a blob file. Values
* which have an uncompressed size smaller than this threshold are stored
* alongside the keys in SST files in the usual fashion. A value of zero for
* this option means that all values are stored in blob files. Note that
* enable_blob_files has to be set in order for this option to have any effect.
*
* Default: 0
*
* Dynamically changeable through
* {@link RocksDB#setOptions(ColumnFamilyHandle, MutableColumnFamilyOptions)}.
*
* @param minBlobSize the size of the smallest value to be stored separately in a blob file
* @return the reference to the current options.
*/
T setMinBlobSize(final long minBlobSize);
/**
* Get the size of the smallest value to be stored separately in a blob file. Values
* which have an uncompressed size smaller than this threshold are stored
* alongside the keys in SST files in the usual fashion. A value of zero for
* this option means that all values are stored in blob files. Note that
* enable_blob_files has to be set in order for this option to have any effect.
*
* Default: 0
*
* Dynamically changeable through
* {@link RocksDB#setOptions(ColumnFamilyHandle, MutableColumnFamilyOptions)}.
*
* @return the current minimum size of value which is stored separately in a blob
*/
long minBlobSize();
/**
* Set the size limit for blob files. When writing blob files, a new file is opened
* once this limit is reached. Note that enable_blob_files has to be set in
* order for this option to have any effect.
*
* Default: 256 MB
*
* Dynamically changeable through
* {@link RocksDB#setOptions(ColumnFamilyHandle, MutableColumnFamilyOptions)}.
*
* @param blobFileSize the size limit for blob files
*
* @return the reference to the current options.
*/
T setBlobFileSize(final long blobFileSize);
/**
* The size limit for blob files. When writing blob files, a new file is opened
* once this limit is reached.
*
* @return the current size limit for blob files
*/
long blobFileSize();
/**
* Set the compression algorithm to use for large values stored in blob files. Note
* that enable_blob_files has to be set in order for this option to have any
* effect.
*
* Default: no compression
*
* Dynamically changeable through
* {@link RocksDB#setOptions(ColumnFamilyHandle, MutableColumnFamilyOptions)}.
*
* @param compressionType the compression algorithm to use.
*
* @return the reference to the current options.
*/
T setBlobCompressionType(CompressionType compressionType);
/**
* Get the compression algorithm in use for large values stored in blob files.
* Note that enable_blob_files has to be set in order for this option to have any
* effect.
*
* @return the current compression algorithm
*/
CompressionType blobCompressionType();
/**
* Enable/disable garbage collection of blobs. Blob GC is performed as part of
* compaction. Valid blobs residing in blob files older than a cutoff get
* relocated to new files as they are encountered during compaction, which makes
* it possible to clean up blob files once they contain nothing but
* obsolete/garbage blobs. See also blob_garbage_collection_age_cutoff below.
*
* Default: false
*
* @param enableBlobGarbageCollection the new enabled/disabled state of blob garbage collection
*
* @return the reference to the current options.
*/
T setEnableBlobGarbageCollection(final boolean enableBlobGarbageCollection);
/**
* Query whether garbage collection of blobs is enabled.Blob GC is performed as part of
* compaction. Valid blobs residing in blob files older than a cutoff get
* relocated to new files as they are encountered during compaction, which makes
* it possible to clean up blob files once they contain nothing but
* obsolete/garbage blobs. See also blob_garbage_collection_age_cutoff below.
*
* Default: false
*
* @return true if blob garbage collection is currently enabled.
*/
boolean enableBlobGarbageCollection();
/**
* Set cutoff in terms of blob file age for garbage collection. Blobs in the
* oldest N blob files will be relocated when encountered during compaction,
* where N = garbage_collection_cutoff * number_of_blob_files. Note that
* enable_blob_garbage_collection has to be set in order for this option to have
* any effect.
*
* Default: 0.25
*
* @param blobGarbageCollectionAgeCutoff the new age cutoff
*
* @return the reference to the current options.
*/
T setBlobGarbageCollectionAgeCutoff(double blobGarbageCollectionAgeCutoff);
/**
* Get cutoff in terms of blob file age for garbage collection. Blobs in the
* oldest N blob files will be relocated when encountered during compaction,
* where N = garbage_collection_cutoff * number_of_blob_files. Note that
* enable_blob_garbage_collection has to be set in order for this option to have
* any effect.
*
* Default: 0.25
*
* @return the current age cutoff for garbage collection
*/
double blobGarbageCollectionAgeCutoff();
/**
* If the ratio of garbage in the oldest blob files exceeds this threshold,
* targeted compactions are scheduled in order to force garbage collecting
* the blob files in question, assuming they are all eligible based on the
* value of {@link #blobGarbageCollectionAgeCutoff} above. This option is
* currently only supported with leveled compactions.
*
* Note that {@link #enableBlobGarbageCollection} has to be set in order for this
* option to have any effect.
*
* Default: 1.0
*
* Dynamically changeable through the SetOptions() API
*
* @param blobGarbageCollectionForceThreshold new value for the threshold
* @return the reference to the current options
*/
T setBlobGarbageCollectionForceThreshold(double blobGarbageCollectionForceThreshold);
/**
* Get the current value for the {@code #blobGarbageCollectionForceThreshold}
* @return the current threshold at which garbage collection of blobs is forced
*/
double blobGarbageCollectionForceThreshold();
/**
* Set compaction readahead for blob files.
*
* Default: 0
*
* Dynamically changeable through
* {@link RocksDB#setOptions(ColumnFamilyHandle, MutableColumnFamilyOptions)}.
*
* @param blobCompactionReadaheadSize the compaction readahead for blob files
*
* @return the reference to the current options.
*/
T setBlobCompactionReadaheadSize(final long blobCompactionReadaheadSize);
/**
* Get compaction readahead for blob files.
*
* @return the current compaction readahead for blob files
*/
long blobCompactionReadaheadSize();
/**
* Set a certain LSM tree level to enable blob files.
*
* Default: 0
*
* Dynamically changeable through
* {@link RocksDB#setOptions(ColumnFamilyHandle, MutableColumnFamilyOptions)}.
*
* @param blobFileStartingLevel the starting level to enable blob files
*
* @return the reference to the current options.
*/
T setBlobFileStartingLevel(final int blobFileStartingLevel);
/**
* Get the starting LSM tree level to enable blob files.
*
* Default: 0
*
* @return the current LSM tree level to enable blob files.
*/
int blobFileStartingLevel();
/**
* Set a certain prepopulate blob cache option.
*
* Default: 0
*
* Dynamically changeable through
* {@link RocksDB#setOptions(ColumnFamilyHandle, MutableColumnFamilyOptions)}.
*
* @param prepopulateBlobCache prepopulate the blob cache option
*
* @return the reference to the current options.
*/
T setPrepopulateBlobCache(final PrepopulateBlobCache prepopulateBlobCache);
/**
* Get the prepopulate blob cache option.
*
* Default: 0
*
* @return the current prepopulate blob cache option.
*/
PrepopulateBlobCache prepopulateBlobCache();
//
// END options for blobs (integrated BlobDB)
//
}