Usage of memory is too high when use default malloc of Ubuntu

gaoxiangxyz commented 5 years ago

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Expected behavior

Usage of memory is normal on both malloc and jemalloc

Actual behavior

The usage of memory is 25GB when use default malloc, but is 13GB when use jemalloc. Memory statistics: block cache: 8.5GB, memtable: 1.5GB, filter/index: 1GB, pinned memory : < 1MB It seems usage of memory is only normal on jemalloc.

Steps to reproduce the behavior

OS: Linux version 4.15.0-45-generic (buildd@lgw01-amd64-031) (gcc version 7.3.0 (Ubuntu 7.3.0-16ubuntu3)) Rocksdb version 5.18.3 Data size is 93G with lz4 compression

config:

options.create_if_missing = true;
options.create_missing_column_families = true;
options.db_write_buffer_size = 1024 * 1024 * 1024;
options.max_background_jobs = 8;
options.max_subcompactions = 4;
options.bytes_per_sync = 1 * 1024 * 1024;
options.compaction_pri = rocksdb::kMinOverlappingRatio;
options.sst_file_manager= rocksdb_sst_file_manager;

column_options.compression = rocksdb::CompressionType::kLZ4Compression;
column_options.prefix_extractor.reset(rocksdb::NewFixedPrefixTransform(3));
column_options.memtable_prefix_bloom_size_ratio = 0.02;
column_options.max_write_buffer_number = 6;
column_options.min_write_buffer_number_to_merge = 2;
column_options.write_buffer_size = 128 * 1024 * 1024;
column_options.max_bytes_for_level_base = 1024 * 1024 * 1024;
column_options.level_compaction_dynamic_level_bytes = true;
column_options.target_file_size_base = 128 * 1024 * 1024;

table_options.block_cache = cache; //8G
table_options.index_type = rocksdb::BlockBasedTableOptions::IndexType::kHashSearch;
table_options.data_block_index_type = rocksdb::BlockBasedTableOptions::DataBlockIndexType::kDataBlockBinaryAndHash;
table_options.filter_policy.reset(rocksdb::NewBloomFilterPolicy(10, false));
table_options.format_version = 4;
table_options.block_size = 16 * 1024;

gaoxiangxyz commented 5 years ago

Jemalloc heap profile: heap

mdcallag commented 5 years ago

This has been an issue with glibc malloc years. I don't think it will be fixed within RocksDB.

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