commonMain.maryk.rocksdb.ColumnFamilyOptions.kt Maven / Gradle / Ivy
package maryk.rocksdb
expect class ColumnFamilyOptions() : RocksObject {
/**
* The minimum number of write buffers that will be merged together
* before writing to storage. If set to 1, then
* all write buffers are flushed to L0 as individual files and this increases
* read amplification because a get request has to check in all of these
* files. Also, an in-memory merge may result in writing lesser
* data to storage if there are duplicate records in each of these
* individual write buffers. Default: 1
*
* @param minWriteBufferNumberToMerge the minimum number of write buffers
* that will be merged together.
* @return the reference to the current options.
*/
fun setMinWriteBufferNumberToMerge(
minWriteBufferNumberToMerge: Int
): ColumnFamilyOptions
/**
* The minimum number of write buffers that will be merged together
* before writing to storage. If set to 1, then
* all write buffers are flushed to L0 as individual files and this increases
* read amplification because a get request has to check in all of these
* files. Also, an in-memory merge may result in writing lesser
* data to storage if there are duplicate records in each of these
* individual write buffers. Default: 1
*
* @return the minimum number of write buffers that will be merged together.
*/
fun minWriteBufferNumberToMerge(): Int
/**
* The total maximum number of write buffers to maintain in memory including
* copies of buffers that have already been flushed. Unlike
* [AdvancedMutableColumnFamilyOptionsInterface.maxWriteBufferNumber],
* this parameter does not affect flushing.
* This controls the minimum amount of write history that will be available
* in memory for conflict checking when Transactions are used.
*
* When using an OptimisticTransactionDB:
* If this value is too low, some transactions may fail at commit time due
* to not being able to determine whether there were any write conflicts.
*
* When using a TransactionDB:
* If Transaction::SetSnapshot is used, TransactionDB will read either
* in-memory write buffers or SST files to do write-conflict checking.
* Increasing this value can reduce the number of reads to SST files
* done for conflict detection.
*
* Setting this value to 0 will cause write buffers to be freed immediately
* after they are flushed.
* If this value is set to -1,
* [AdvancedMutableColumnFamilyOptionsInterface.maxWriteBufferNumber]
* will be used.
*
* Default:
* If using a TransactionDB/OptimisticTransactionDB, the default value will
* be set to the value of
* [AdvancedMutableColumnFamilyOptionsInterface.maxWriteBufferNumber]
* if it is not explicitly set by the user. Otherwise, the default is 0.
*
* @param maxWriteBufferNumberToMaintain The maximum number of write
* buffers to maintain
*
* @return the reference to the current options.
*/
fun setMaxWriteBufferNumberToMaintain(
maxWriteBufferNumberToMaintain: Int
): ColumnFamilyOptions
/**
* The total maximum number of write buffers to maintain in memory including
* copies of buffers that have already been flushed.
*
* @return maxWriteBufferNumberToMaintain The maximum number of write buffers
* to maintain
*/
fun maxWriteBufferNumberToMaintain(): Int
/**
* Control locality of bloom filter probes to improve cache miss rate.
* This option only applies to memtable prefix bloom and plaintable
* prefix bloom. It essentially limits the max number of cache lines each
* bloom filter check can touch.
* This optimization is turned off when set to 0. The number should never
* be greater than number of probes. This option can boost performance
* for in-memory workload but should use with care since it can cause
* higher false positive rate.
* Default: 0
*
* @param bloomLocality the level of locality of bloom-filter probes.
* @return the reference to the current options.
*/
fun setBloomLocality(bloomLocality: Int): ColumnFamilyOptions
/**
* Control locality of bloom filter probes to improve cache miss rate.
* This option only applies to memtable prefix bloom and plaintable
* prefix bloom. It essentially limits the max number of cache lines each
* bloom filter check can touch.
* This optimization is turned off when set to 0. The number should never
* be greater than number of probes. This option can boost performance
* for in-memory workload but should use with care since it can cause
* higher false positive rate.
* Default: 0
*
* @return the level of locality of bloom-filter probes.
* @see .setBloomLocality
*/
fun bloomLocality(): Int
/**
* Set the number of levels for this database
* If level-styled compaction is used, then this number determines
* the total number of levels.
*
* @param numLevels the number of levels.
* @return the reference to the current options.
*/
fun setNumLevels(numLevels: Int): ColumnFamilyOptions
/**
* If level-styled compaction is used, then this number determines
* the total number of levels.
*
* @return the number of levels.
*/
fun numLevels(): Int
/**
* Set compaction style for DB.
*
* Default: LEVEL.
*
* @param compactionStyle Compaction style.
* @return the reference to the current options.
*/
fun setCompactionStyle(
compactionStyle: CompactionStyle
): ColumnFamilyOptions
/**
* Compaction style for DB.
*
* @return Compaction style.
*/
fun compactionStyle(): CompactionStyle
/**
* Set [BuiltinComparator] to be used with RocksDB.
*
* Note: Comparator can be set once upon database creation.
*
* Default: BytewiseComparator.
* @param builtinComparator a [BuiltinComparator] type.
* @return the instance of the current object.
*/
fun setComparator(
builtinComparator: BuiltinComparator
): ColumnFamilyOptions
/**
* Use the specified comparator for key ordering.
*
* Comparator should not be disposed before options instances using this comparator is
* disposed. If dispose() function is not called, then comparator object will be
* GC'd automatically.
*
* Comparator instance can be re-used in multiple options instances.
*
* @param comparator instance.
* @return the instance of the current object.
*/
fun setComparator(
comparator: AbstractComparator
): ColumnFamilyOptions
/**
* This prefix-extractor uses the first n bytes of a key as its prefix.
*
* In some hash-based memtable representation such as HashLinkedList
* and HashSkipList, prefixes are used to partition the keys into
* several buckets. Prefix extractor is used to specify how to
* extract the prefix given a key.
*
* @param n use the first n bytes of a key as its prefix.
* @return the reference to the current option.
*/
fun useFixedLengthPrefixExtractor(n: Int): ColumnFamilyOptions
/**
* 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 option.
*/
fun setMaxBytesForLevelMultiplier(
multiplier: Double
): ColumnFamilyOptions
/**
* 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.
*/
fun maxBytesForLevelMultiplier(): Double
/**
* Amount of data to build up in memory (backed by an unsorted log
* on disk) before converting to a sorted on-disk file.
*
* Larger values increase performance, especially during bulk loads.
* Up to `max_write_buffer_number` write buffers may be held in memory
* at the same time, so you may wish to adjust this parameter
* to control memory usage.
*
* Also, a larger write buffer will result in a longer recovery time
* the next time the database is opened.
*
* Default: 4MB
* @param writeBufferSize the size of write buffer.
* @return the instance of the current object.
* @throws java.lang.IllegalArgumentException thrown on 32-Bit platforms
* while overflowing the underlying platform specific value.
*/
fun setWriteBufferSize(writeBufferSize: Long): ColumnFamilyOptions
/**
* Return size of write buffer size.
*
* @return size of write buffer.
* @see .setWriteBufferSize
*/
fun writeBufferSize(): Long
/**
* Disable automatic compactions. Manual compactions can still
* be issued on this column family
*
* @param disableAutoCompactions true if auto-compactions are disabled.
* @return the reference to the current option.
*/
fun setDisableAutoCompactions(
disableAutoCompactions: Boolean
): ColumnFamilyOptions
/**
* Disable automatic compactions. Manual compactions can still
* be issued on this column family
*
* @return true if auto-compactions are disabled.
*/
fun disableAutoCompactions(): Boolean
/**
* Number of files to trigger level-0 compaction. A value < 0 means that
* level-0 compaction will not be triggered by number of files at all.
*
* Default: 4
*
* @param level0FileNumCompactionTrigger The number of files to trigger
* level-0 compaction
* @return the reference to the current option.
*/
fun setLevel0FileNumCompactionTrigger(
level0FileNumCompactionTrigger: Int
): ColumnFamilyOptions
/**
* Number of files to trigger level-0 compaction. A value < 0 means that
* level-0 compaction will not be triggered by number of files at all.
*
* Default: 4
*
* @return The number of files to trigger
*/
fun level0FileNumCompactionTrigger(): Int
/**
* The upper-bound of the total size of level-1 files in bytes.
* Maximum number of bytes for level L can be calculated as
* (maxBytesForLevelBase) * (maxBytesForLevelMultiplier ^ (L-1))
* For example, if maxBytesForLevelBase is 20MB, and if
* max_bytes_for_level_multiplier is 10, total data size for level-1
* will be 20MB, total file size for level-2 will be 200MB,
* and total file size for level-3 will be 2GB.
* by default 'maxBytesForLevelBase' is 10MB.
*
* @param maxBytesForLevelBase maximum bytes for level base.
*
* @return the reference to the current option.
*
* See [AdvancedMutableColumnFamilyOptionsInterface.setMaxBytesForLevelMultiplier]
*/
fun setMaxBytesForLevelBase(
maxBytesForLevelBase: Long
): ColumnFamilyOptions
/**
* The upper-bound of the total size of level-1 files in bytes.
* Maximum number of bytes for level L can be calculated as
* (maxBytesForLevelBase) * (maxBytesForLevelMultiplier ^ (L-1))
* For example, if maxBytesForLevelBase is 20MB, and if
* max_bytes_for_level_multiplier is 10, total data size for level-1
* will be 20MB, total file size for level-2 will be 200MB,
* and total file size for level-3 will be 2GB.
* by default 'maxBytesForLevelBase' is 10MB.
*
* @return the upper-bound of the total size of level-1 files
* in bytes.
*
* See [AdvancedMutableColumnFamilyOptionsInterface.maxBytesForLevelMultiplier]
*/
fun maxBytesForLevelBase(): Long
/**
* Compress blocks using the specified compression algorithm. This
* parameter can be changed dynamically.
*
* Default: SNAPPY_COMPRESSION, which gives lightweight but fast compression.
*
* @param compressionType Compression Type.
* @return the reference to the current option.
*/
fun setCompressionType(
compressionType: CompressionType
): ColumnFamilyOptions
/**
* Compress blocks using the specified compression algorithm. This
* parameter can be changed dynamically.
*
* Default: SNAPPY_COMPRESSION, which gives lightweight but fast compression.
*
* @return Compression type.
*/
fun compressionType(): CompressionType
/**
* 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.
*/
fun setMaxWriteBufferNumber(
maxWriteBufferNumber: Int
): ColumnFamilyOptions
/**
* Returns maximum number of write buffers.
*
* @return maximum number of write buffers.
* @see .setMaxWriteBufferNumber
*/
fun maxWriteBufferNumber(): Int
/**
* 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 santinized to 0.25.
*
* Default: 0 (disable)
*
* @param memtablePrefixBloomSizeRatio The ratio
* @return the reference to the current options.
*/
fun setMemtablePrefixBloomSizeRatio(
memtablePrefixBloomSizeRatio: Double
): ColumnFamilyOptions
/**
* 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 santinized to 0.25.
*
* Default: 0 (disable)
*
* @return the ratio
*/
fun memtablePrefixBloomSizeRatio(): Double
/**
* 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.
*/
fun setMemtableHugePageSize(
memtableHugePageSize: Long
): ColumnFamilyOptions
/**
* 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
*/
fun memtableHugePageSize(): Long
/**
* 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.
*/
fun setArenaBlockSize(arenaBlockSize: Long): ColumnFamilyOptions
/**
* 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
*/
fun arenaBlockSize(): Long
/**
* 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.
*/
fun setLevel0SlowdownWritesTrigger(
level0SlowdownWritesTrigger: Int
): ColumnFamilyOptions
/**
* 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
*/
fun level0SlowdownWritesTrigger(): Int
/**
* 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.
*/
fun setLevel0StopWritesTrigger(
level0StopWritesTrigger: Int
): ColumnFamilyOptions
/**
* Maximum number of level-0 files. We stop writes at this point.
*
* @return The maximum number of level-0 files
*/
fun level0StopWritesTrigger(): Int
/**
* 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 2MB.
*
* @param targetFileSizeBase the target size of a level-0 file.
* @return the reference to the current options.
*
* @see .setTargetFileSizeMultiplier
*/
fun setTargetFileSizeBase(
targetFileSizeBase: Long
): ColumnFamilyOptions
/**
* 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 2MB.
*
* @return the target size of a level-0 file.
*
* @see .targetFileSizeMultiplier
*/
fun targetFileSizeBase(): Long
/**
* 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.
*/
fun setTargetFileSizeMultiplier(
multiplier: Int
): ColumnFamilyOptions
/**
* 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.
*/
fun targetFileSizeMultiplier(): Int
/**
* 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 a iteration.
* @return the reference to the current options.
*/
fun setMaxSequentialSkipInIterations(
maxSequentialSkipInIterations: Long
): ColumnFamilyOptions
/**
* 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 a iteration.
*/
fun maxSequentialSkipInIterations(): Long
/**
* 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.
*/
fun setMaxSuccessiveMerges(
maxSuccessiveMerges: Long
): ColumnFamilyOptions
/**
* 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.
*/
fun maxSuccessiveMerges(): Long
}
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