Shortens blocks' last_key in the SSTable block index. #1361
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| // It is possible to do one character shorter in some case, | ||
| // but it is not worth the extra complexity | ||
| for pos in (common_len + 1)..left.len() { | ||
| if left[pos] != 255u8 { |
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what's the meaning of 255 here?
the comment says string, but we operate on bytes, what about utf-8?
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255 is the max value for a u8.
It is not especially utf8. All of these are byte strings.
There are already u64 byte representation in there.
We do not expose the last term in block so it should be safe.
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Codecov Report
@@ Coverage Diff @@
## main #1361 +/- ##
========================================
Coverage 94.28% 94.29%
========================================
Files 234 234
Lines 42528 42634 +106
========================================
+ Hits 40099 40201 +102
- Misses 2429 2433 +4
Continue to review full report at Codecov.
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Right now we store last key in the blocks of the SSTable index. This PR replaces the last key by a shorter string that is greater or equal and still lesser than the next key. This property is sufficiently to ensure the block index works properly. Related to quickwit#1366
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Co-authored-by: PSeitz <PSeitz@users.noreply.github.com>
Co-authored-by: PSeitz <PSeitz@users.noreply.github.com>
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This was referenced Jan 13, 2023
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Right now we store last key in the blocks of the SSTable index.
This PR replaces the last key by a shorter string that is greater or
equal and still lesser than the next key.
This property is sufficiently to ensure the block index
works properly.