可以通过设置 RocksDB 的 use_direct_reads 参数来使用 direct io 读，这样就绕过系统的 page cache，...
//创建迭代器 rocksdb::Iterator* it = db->NewIterator(option); //Seek与Next移动迭代器 for (...
--use_direct_reads=0 --use_direct_io_for_flush_and_compaction=0 \ --disable_wal=1 --verify_checksum=1 \ --stats_per_interval=1 --stats_interval_seconds=60 --histogram=1 The readrandom workload The readrandom workload randomly reads data from an existing database. The numbe...
DB大小为86G,HDD存储,在一个具有100TB数据的node上模拟小内存,使用Direct IO(关闭OS file cache),block cache大小设置为60MB。分片后吞吐提升了11倍( 5 op/s提升到55 op/s)。 /db_bench--benchmarks="readwhilewriting[X3],stats"--use_direct_reads=1-compaction_readahead_size1048576--use_existing_db...
406 // disabled (ReadOptions::fill_cache = false) and direct IO is 407 // enabled (DBOptions::use_direct_reads = true). 408 // The default mode is the best tradeoff for most use cases. 409 // This option only affects newly written tables. 410 // 411 // The index contains a...
rocksdb.use_direct_reads | false | Enable the OS to use direct I/O for reading sst tables. rocksdb.write_buffer_size | 134217728 | Amount of data in bytes to build up in memory. rocksdb.max_manifest_file_size | 104857600 | The max size of manifest file in bytes. rocksdb.skip_stat...
.setUseDirectReads(true); } 代码示例来源:origin: org.apache.kylin/kylin-core-dictionary public RocksDBLookupBuilder(TableDesc tableDesc, String[] keyColumns, String dbPath) { this.tableDesc = tableDesc; this.encoder = new RocksDBLookupRowEncoder(tableDesc, keyColumns); this.dbPath = dbPath; ...
Options::use_direct_writes and Options::use_direct_reads are now ready to use. (Experimental) Two-level indexing that partition the index and creates a 2nd level index on the partitions. The feature can be enabled by setting kTwoLevelIndexSearch as IndexType and configuring index_per_partition...
RocksDB uses a LRU cache for blocks to serve reads. The block cache is partitioned into two individual caches: the first caches uncompressed blocks and the second caches compressed blocks in RAM. If a compressed block cache is configured, users may wish to enable direct I/O to prevent redun...
(PMDK)is a growing collection of libraries developed for various use cases, tuned, validated to production quality, and thoroughly documented. These libraries build on the Direct Access (DAX) feature available in both Linux and Windows, which allows applications direct loa...