release-20.2: sql/rowexec: don't allocate buf per row in sketchInfo.addRow #58197
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The `intbuf` array was meant to stay on the stack, but was escaping to the heap because the call through the `hash` function variable was opaque to escape analysis. At the end of a 4 hour, 2.2 TB IMPORT of TPC-E, this was responsible for **76.70%** of all heap allocations. Release note (performance improvement): SQL statistics collection has been made more efficient by avoiding an accidental heap allocation per row for some schemas.
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RaduBerinde
approved these changes
Dec 22, 2020
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Backport 1/1 commits from #58117.
/cc @cockroachdb/release
The
intbufarray was meant to stay on the stack, but was escaping to the heap because the call through thehashfunction variable was opaque to escape analysis.At the end of a 4 hour, 2.2 TB IMPORT of TPC-E, this was responsible for 76.70% of all heap allocations (by object).
Release note (performance improvement): SQL statistics collection has been made more efficient by avoiding an accidental heap allocation per row for some schemas.