More details for 'tail prefetch size is calculated based on' #12667
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It is a warning so we can track use cases that are at risk of regression when we finally remove TailPrefetchStats. The warnings and the risk can be mitigated by running compaction with a new enough RocksDB version (see #12664). If you still wanted to make a code change here, may I suggest a couple ideas:
- As you mentioned the documentation was inadequate to know what to do. Maybe the warning text or surrounding comments could be improved.
- Deduplicating the error could help with the spam problem. Maybe one warning per DB open saying N files are at risk.
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andlr
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Thanks for the explanation. I think in such case, it's probably enough to add name of the SST file into the log message, and a comment in code, saying that this backward compatibility won't be preserved forever |
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These messages indicate that SST file was created by a pre-9.0.0 RocksDB. Eventually,
TailPrefetchStatsmight be removed, so it would be more informative if log message also included name of the affected SST file.Issue: #12664