mirror of https://github.com/facebook/rocksdb.git
3d67b5e8e5
Summary: Implement block cache lookup to determine readahead_size during scans. It's enabled if auto_readahead_size, block_cache and iterate_upper_bound - all three are set. Design - 1. Whenever there is a cache miss and FilePrefetchBuffer is called, a callback is made to determine readahead_size for that prefetching. 2. The callback iterates over index and do block cache lookup for each data block handle until existing readahead_size is reached. Then It removes the cache hit data blocks from end to calculate optimized readahead_size. 3. Since index_iter_ is moved, it stores block handles in a queue, and use that queue to get block handle instead of doing index_iter_->Next(). 4. This is for Sync scans. Async scans support is in progress. NOTE: The issue right now is after Seek and Next, if Prev is called, there is no way to do Prev operation. index_iter_ is already pointing to a different block. So it returns "Not supported" in that case with error message - "auto tuning of readahead size is not supported with Prev op" Pull Request resolved: https://github.com/facebook/rocksdb/pull/11860 Test Plan: - Added new unit test - crash_tests - Running scans locally to check for any regression Reviewed By: anand1976 Differential Revision: D49548118 Pulled By: akankshamahajan15 fbshipit-source-id: f1aee409a71b4ad9e5bf3610f43edf30c6630c78 |
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| .. | ||
| delete_scheduler.cc | ||
| delete_scheduler.h | ||
| delete_scheduler_test.cc | ||
| file_prefetch_buffer.cc | ||
| file_prefetch_buffer.h | ||
| file_util.cc | ||
| file_util.h | ||
| filename.cc | ||
| filename.h | ||
| line_file_reader.cc | ||
| line_file_reader.h | ||
| prefetch_test.cc | ||
| random_access_file_reader.cc | ||
| random_access_file_reader.h | ||
| random_access_file_reader_test.cc | ||
| read_write_util.cc | ||
| read_write_util.h | ||
| readahead_file_info.h | ||
| readahead_raf.cc | ||
| readahead_raf.h | ||
| sequence_file_reader.cc | ||
| sequence_file_reader.h | ||
| sst_file_manager_impl.cc | ||
| sst_file_manager_impl.h | ||
| writable_file_writer.cc | ||
| writable_file_writer.h | ||