C++: Restructure UnsafeUseOfStrcat for performance#183
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This query gets optimized badly, and it has started timing out when we run it on our own code base. Most of the evaluation time is spent in an RA predicate named `#select#cpe#1#f#antijoin_rhs#1`, which takes 1m36s a Wireshark snapshot. This restructuring of the code makes the problematic RA predicate go away.
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This looks like a safe change to me. I briefly tried it out locally on three snapshots: Some of that is probably just variance but the last result looks promising. |
geoffw0
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Sep 12, 2018
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LGTM, see my previous comment.
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C#: Add a hash-cons library for C#
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This query gets optimized badly, and it has started timing out when we run it on our own code base. Most of the evaluation time is spent in an RA predicate named
#select#cpe#1#f#antijoin_rhs#1, which takes 1m36s a Wireshark snapshot.This restructuring of the code makes the problematic RA predicate go away.
I'm targetting 1.18 here because if this query can cause timeouts on our internal dashboard then I worry that it's an observable regression since 1.17. I haven't actually been able to reproduce the timeout from the Dashboards/Internal Jenkins job, so this change may or may not fix it, but nothing else seems slow about this query.