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    Account memory of big memory users in BlockBasedTable in global memory limit (#9748) · 49623f9c
    Hui Xiao 提交于
    Summary:
    **Context:**
    Through heap profiling, we discovered that `BlockBasedTableReader` objects can accumulate and lead to high memory usage (e.g, `max_open_file = -1`). These memories are currently not saved, not tracked, not constrained and not cache evict-able. As a first step to improve this, similar to https://github.com/facebook/rocksdb/pull/8428,  this PR is to track an estimate of `BlockBasedTableReader` object's memory in block cache and fail future creation if the memory usage exceeds the available space of cache at the time of creation.
    
    **Summary:**
    - Approximate big memory users  (`BlockBasedTable::Rep` and `TableProperties` )' memory usage in addition to the existing estimated ones (filter block/index block/un-compression dictionary)
    - Charge all of these memory usages to block cache on `BlockBasedTable::Open()` and release them on `~BlockBasedTable()` as there is no memory usage fluctuation of concern in between
    - Refactor on CacheReservationManager (and its call-sites) to add concurrent support for BlockBasedTable  used in this PR.
    
    Pull Request resolved: https://github.com/facebook/rocksdb/pull/9748
    
    Test Plan:
    - New unit tests
    - db bench: `OpenDb` : **-0.52% in ms**
      - Setup `./db_bench -benchmarks=fillseq -db=/dev/shm/testdb -disable_auto_compactions=1 -write_buffer_size=1048576`
      - Repeated run with pre-change w/o feature and post-change with feature, benchmark `OpenDb`:  `./db_bench -benchmarks=readrandom -use_existing_db=1 -db=/dev/shm/testdb -reserve_table_reader_memory=true (remove this when running w/o feature) -file_opening_threads=3 -open_files=-1 -report_open_timing=true| egrep 'OpenDb:'`
    
    #-run | (feature-off) avg milliseconds | std milliseconds | (feature-on) avg milliseconds | std milliseconds | change (%)
    -- | -- | -- | -- | -- | --
    10 | 11.4018 | 5.95173 | 9.47788 | 1.57538 | -16.87382694
    20 | 9.23746 | 0.841053 | 9.32377 | 1.14074 | 0.9343477536
    40 | 9.0876 | 0.671129 | 9.35053 | 1.11713 | 2.893283155
    80 | 9.72514 | 2.28459 | 9.52013 | 1.0894 | -2.108041632
    160 | 9.74677 | 0.991234 | 9.84743 | 1.73396 | 1.032752389
    320 | 10.7297 | 5.11555 | 10.547 | 1.97692 | **-1.70275031**
    640 | 11.7092 | 2.36565 | 11.7869 | 2.69377 | **0.6635807741**
    
    -  db bench on write with cost to cache in WriteBufferManager (just in case this PR's CRM refactoring accidentally slows down anything in WBM) : `fillseq` : **+0.54% in micros/op**
    `./db_bench -benchmarks=fillseq -db=/dev/shm/testdb -disable_auto_compactions=1 -cost_write_buffer_to_cache=true -write_buffer_size=10000000000 | egrep 'fillseq'`
    
    #-run | (pre-PR) avg micros/op | std micros/op | (post-PR)  avg micros/op | std micros/op | change (%)
    -- | -- | -- | -- | -- | --
    10 | 6.15 | 0.260187 | 6.289 | 0.371192 | 2.260162602
    20 | 7.28025 | 0.465402 | 7.37255 | 0.451256 | 1.267813605
    40 | 7.06312 | 0.490654 | 7.13803 | 0.478676 | **1.060579461**
    80 | 7.14035 | 0.972831 | 7.14196 | 0.92971 | **0.02254791432**
    
    -  filter bench: `bloom filter`: **-0.78% in ms/key**
        - ` ./filter_bench -impl=2 -quick -reserve_table_builder_memory=true | grep 'Build avg'`
    
    #-run | (pre-PR) avg ns/key | std ns/key | (post-PR)  ns/key | std ns/key | change (%)
    -- | -- | -- | -- | -- | --
    10 | 26.4369 | 0.442182 | 26.3273 | 0.422919 | **-0.4145720565**
    20 | 26.4451 | 0.592787 | 26.1419 | 0.62451 | **-1.1465262**
    
    - Crash test `python3 tools/db_crashtest.py blackbox --reserve_table_reader_memory=1 --cache_size=1` killed as normal
    
    Reviewed By: ajkr
    
    Differential Revision: D35136549
    
    Pulled By: hx235
    
    fbshipit-source-id: 146978858d0f900f43f4eb09bfd3e83195e3be28
    49623f9c
block_based_table_reader.h 32.2 KB