Compaction: Restore SetupForCompaction functionality #788
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In facebook/rocksdb#11658, files are no longer controlled by the access_hint_on_compaction_start flag by removing the content of SetupForCompaction. However, this leads to degradation in compaction read speed when combined with compaction_readahead_size since once a file is opened, in linux, it is hinted with POSIX_FADV_RANDOM. See #787 for full details. Add back the default hint to avoid degradation in this scenario.
ofriedma
approved these changes
Dec 28, 2023
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In facebook/rocksdb#11658, files are no longer controlled by the access_hint_on_compaction_start flag by removing the content of SetupForCompaction. However, this leads to degradation in compaction read speed when combined with compaction_readahead_size since once a file is opened, in linux, it is hinted with POSIX_FADV_RANDOM.
See #787 for full details.
Add back the default hint to avoid degradation in this scenario.