Fix sharded indexing dropping segments with negative hashCode#3334
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yashs33244 wants to merge 1 commit into
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Fix sharded indexing dropping segments with negative hashCode#3334yashs33244 wants to merge 1 commit into
yashs33244 wants to merge 1 commit into
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…(use Math.floorMod)
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getSegmentPaths(shardCount, currShard)filtered withx.toString().hashCode() % shardCount == currShard. Java%keeps the dividend's sign andString.hashCode()is negative for roughly half of inputs, so the result can be negative and match nocurrShardin[0, shardCount-1]. Those segments are then indexed by no shard and silently dropped (a quick check drops ~half of segments on a random set).Switched to
Math.floorMod(...)inDocumentCollectionand in theC4Collectionoverride (whoseNumberFormatExceptionfallback also returns a rawhashCode()). Added atestShardedPartitionregression test asserting the shards partition the collection: every segment lands in exactly one shard (complete and disjoint). It runs for all collection subclasses.