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Account for per-leaf codec overhead exactly - #28
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IncidenceCodec charged one byte per entry for its flags byte and column bitmaps, which undercounted leaves under 8 entries and only worked because of the layout reserve. Codecs can now declare a per-leaf overhead, and leaf sizes and bulk building include it.
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Closes #14
IncidenceCodec.maxSizecharged one byte per entry to cover the flags byte and the column bitmaps. For leaves under 8 entries that came up short by up to 7 bytes, and it only worked becauseLayoutkeeps a 32-byte reserve.ValueCodecnow has aleafOverhead(entries)hook (0 by default).IncidenceCodecreturns1 + columns * ceil(n / 8)and no longer adds a byte per entry.Leaf.bytes()andBulkBuilderinclude the overhead when deciding splits. The reserve is still there, but nothing relies on it anymore.For large leaves the new bound is a bit tighter than before (
1 + 6 * ceil(n/8)instead ofn), so leaves can hold slightly more entries. The on-disk encoding doesn't change.IncidenceCodecTest:Full
./mvnw installpasses locally, including the crash matrix.