rocksdb/table
Akanksha Mahajan 04b2c16f9b Fix bug in rocksdb internal automatic prefetching (#9234)
Summary:
After introducing adaptive_readahead, the original flow got
broken. Readahead size was set to 0 because of which rocksdb wasn't be
able to do automatic prefetching which it enables after seeing
sequential reads. This PR fixes it.

----------------------------------------------------------------------------------------------------

Before this patch:
b_bench -use_existing_db=true -db=/tmp/prefix_scan -benchmarks="seekrandom" -key_size=32 -value_size=512 -num=5000000 -use_direct_reads=true -seek_nexts=327680 -duration=120 -ops_between_duration_checks=1
Initializing RocksDB Options from the specified file
Initializing RocksDB Options from command-line flags
RocksDB:    version 6.27
Date:       Tue Nov 30 11:56:50 2021
CPU:        24 * Intel Core Processor (Broadwell)
CPUCache:   16384 KB
Keys:       32 bytes each (+ 0 bytes user-defined timestamp)
Values:     512 bytes each (256 bytes after compression)
Entries:    5000000
Prefix:    0 bytes
Keys per prefix:    0
RawSize:    2594.0 MB (estimated)
FileSize:   1373.3 MB (estimated)
Write rate: 0 bytes/second
Read rate: 0 ops/second
Compression: Snappy
Compression sampling rate: 0
Memtablerep: SkipListFactory
Perf Level: 1
WARNING: Assertions are enabled; benchmarks unnecessarily slow
------------------------------------------------
DB path: [/tmp/prefix_scan]

seekrandom   : 5356367.174 micros/op 0 ops/sec;   29.4 MB/s (23 of 23 found)

----------------------------------------------------------------------------------------------------

After the patch:
./db_bench -use_existing_db=true -db=/tmp/prefix_scan -benchmarks="seekrandom" -key_size=32 -value_size=512 -num=5000000 -use_direct_reads=true -seek_nexts=327680 -duration=120 -ops_between_duration_checks=1
Initializing RocksDB Options from the specified file
Initializing RocksDB Options from command-line flags
RocksDB:    version 6.27
Date:       Tue Nov 30 14:38:33 2021
CPU:        24 * Intel Core Processor (Broadwell)
CPUCache:   16384 KB
Keys:       32 bytes each (+ 0 bytes user-defined timestamp)
Values:     512 bytes each (256 bytes after compression)
Entries:    5000000
Prefix:    0 bytes
Keys per prefix:    0
RawSize:    2594.0 MB (estimated)
FileSize:   1373.3 MB (estimated)
Write rate: 0 bytes/second
Read rate: 0 ops/second
Compression: Snappy
Compression sampling rate: 0
Memtablerep: SkipListFactory
Perf Level: 1
WARNING: Assertions are enabled; benchmarks unnecessarily slow
------------------------------------------------
DB path: [/tmp/prefix_scan]
seekrandom   :  456504.277 micros/op 2 ops/sec;  359.8 MB/s (264 of 264 found)

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9234

Test Plan:
Ran ./db_bench -db=/data/mysql/rocksdb/prefix_scan
-benchmarks="fillseq" -key_size=32 -value_size=512 -num=5000000 -use_d
irect_io_for_flush_and_compaction=true -target_file_size_base=16777216
and then ./db_bench -use_existing_db=true
-db=/data/mysql/rocksdb/prefix_scan -benchmarks="seekrandom"
-key_size=32 -value_siz
e=512 -num=5000000 -use_direct_reads=true -seek_nexts=327680
-duration=120 -ops_between_duration_checks=1
 and compared the results.

Reviewed By: anand1976

Differential Revision: D32743965

Pulled By: akankshamahajan15

fbshipit-source-id: b950fba68c91963b7deb5c20acdf471bc60251f5
2021-11-30 22:53:10 -08:00
..
adaptive Refactor: use TableBuilderOptions to reduce parameter lists (#8240) 2021-04-29 07:00:50 -07:00
block_based Fix bug in rocksdb internal automatic prefetching (#9234) 2021-11-30 22:53:10 -08:00
cuckoo Improve / clean up meta block code & integrity (#9163) 2021-11-18 11:43:44 -08:00
plain Improve / clean up meta block code & integrity (#9163) 2021-11-18 11:43:44 -08:00
block_fetcher_test.cc Cleanup includes in dbformat.h (#8930) 2021-09-29 04:04:40 -07:00
block_fetcher.cc Support readahead during compaction for blob files (#9187) 2021-11-19 17:53:47 -08:00
block_fetcher.h Improve / clean up meta block code & integrity (#9163) 2021-11-18 11:43:44 -08:00
cleanable_test.cc Replace namespace name "rocksdb" with ROCKSDB_NAMESPACE (#6433) 2020-02-20 12:09:57 -08:00
format.cc Support readahead during compaction for blob files (#9187) 2021-11-19 17:53:47 -08:00
format.h Improve / clean up meta block code & integrity (#9163) 2021-11-18 11:43:44 -08:00
get_context.cc Support readahead during compaction for blob files (#9187) 2021-11-19 17:53:47 -08:00
get_context.h Cleanup includes in dbformat.h (#8930) 2021-09-29 04:04:40 -07:00
internal_iterator.h Reuse internal auto readhead_size at each Level (expect L0) for Iterations (#9056) 2021-11-10 16:20:04 -08:00
iter_heap.h Replace namespace name "rocksdb" with ROCKSDB_NAMESPACE (#6433) 2020-02-20 12:09:57 -08:00
iterator_wrapper.h Reuse internal auto readhead_size at each Level (expect L0) for Iterations (#9056) 2021-11-10 16:20:04 -08:00
iterator.cc Replace namespace name "rocksdb" with ROCKSDB_NAMESPACE (#6433) 2020-02-20 12:09:57 -08:00
merger_test.cc Cleanup multiple implementations of VectorIterator (#8901) 2021-10-06 07:48:31 -07:00
merging_iterator.cc MergingIterator: rearrange fields to reduce paddings (#9024) 2021-10-14 12:01:56 -07:00
merging_iterator.h Cleanup includes in dbformat.h (#8930) 2021-09-29 04:04:40 -07:00
meta_blocks.cc Fix backward compatibility with 2.5 through 2.7 (#9189) 2021-11-19 17:31:01 -08:00
meta_blocks.h Improve / clean up meta block code & integrity (#9163) 2021-11-18 11:43:44 -08:00
mock_table.cc Introduce a mechanism to dump out blocks from block cache and re-insert to secondary cache (#8912) 2021-10-07 11:42:31 -07:00
mock_table.h Fix some minor issues in the Customizable infrastructure (#8566) 2021-08-19 10:10:47 -07:00
multiget_context.h Batch blob read IO for MultiGet (#8699) 2021-09-17 19:23:13 -07:00
persistent_cache_helper.cc Improve / clean up meta block code & integrity (#9163) 2021-11-18 11:43:44 -08:00
persistent_cache_helper.h Replace namespace name "rocksdb" with ROCKSDB_NAMESPACE (#6433) 2020-02-20 12:09:57 -08:00
persistent_cache_options.h Improve / clean up meta block code & integrity (#9163) 2021-11-18 11:43:44 -08:00
scoped_arena_iterator.h Replace namespace name "rocksdb" with ROCKSDB_NAMESPACE (#6433) 2020-02-20 12:09:57 -08:00
sst_file_dumper.cc Support readahead during compaction for blob files (#9187) 2021-11-19 17:53:47 -08:00
sst_file_dumper.h Make ImmutableOptions struct that inherits from ImmutableCFOptions and ImmutableDBOptions (#8262) 2021-05-05 14:00:17 -07:00
sst_file_reader_test.cc Enable a few unit tests to use custom Env objects (#9087) 2021-11-08 11:05:59 -08:00
sst_file_reader.cc Make ImmutableOptions struct that inherits from ImmutableCFOptions and ImmutableDBOptions (#8262) 2021-05-05 14:00:17 -07:00
sst_file_writer_collectors.h Cleanup includes in dbformat.h (#8930) 2021-09-29 04:04:40 -07:00
sst_file_writer.cc Support timestamps in SstFileWriter (#8899) 2021-09-09 18:58:01 -07:00
table_builder.h Partially revert the "apply subrange of table property collectors" change (#8465) 2021-07-06 10:14:32 -07:00
table_factory.cc Add customizable_util.h to the public API (#8301) 2021-06-29 09:08:57 -07:00
table_properties_internal.h Improve / clean up meta block code & integrity (#9163) 2021-11-18 11:43:44 -08:00
table_properties.cc Improve / clean up meta block code & integrity (#9163) 2021-11-18 11:43:44 -08:00
table_reader_bench.cc Make it possible to apply only a subrange of table property collectors (#8298) 2021-05-17 18:28:39 -07:00
table_reader_caller.h Fix and detect headers with missing dependencies (#8893) 2021-09-10 10:00:26 -07:00
table_reader.h dedup ReadOptions in iterator hierarchy (#7210) 2020-08-03 15:23:04 -07:00
table_test.cc Support readahead during compaction for blob files (#9187) 2021-11-19 17:53:47 -08:00
two_level_iterator.cc Clarify caching behavior for index and filter partitions (#9068) 2021-10-27 17:23:04 -07:00
two_level_iterator.h Replace namespace name "rocksdb" with ROCKSDB_NAMESPACE (#6433) 2020-02-20 12:09:57 -08:00
unique_id_impl.h Experimental support for SST unique IDs (#8990) 2021-10-18 23:32:01 -07:00
unique_id.cc Experimental support for SST unique IDs (#8990) 2021-10-18 23:32:01 -07:00