Fix an optimization in terms agg #57438
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When the `terms` agg runs against strings and uses global ordinals it has an optimization when it collects segments that only ever have a single value for the particular string. This is *very* common. But I broke it in elastic#57241. This fixes that optimization and adds `debug` information that you can use to see how often we collect segments of each type. And adds a test to make sure that I don't break the optimization again. We also had a specialiation for when there isn't a filter on the terms to aggregate. I had removed that specialization in elastic#57241 which resulted in some slow down as well. This adds it back but in a more clear way. And, hopefully, a way that is marginally faster when there *is* a filter. Closes elastic#57407
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Pinging @elastic/es-analytics-geo (:Analytics/Aggregations) |
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I've labeled this non-issue because it fixes a unreleased performance regression. Thanks for finding it @dliappis ! |
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not-napoleon
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LGTM. If at some point you'd like to make a flow chart of what choices terms makes to decide on its leaf collector implementation, I'd find that helpful.
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Good call! |
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When the `terms` agg runs against strings and uses global ordinals it has an optimization when it collects segments that only ever have a single value for the particular string. This is *very* common. But I broke it in elastic#57241. This fixes that optimization and adds `debug` information that you can use to see how often we collect segments of each type. And adds a test to make sure that I don't break the optimization again. We also had a specialiation for when there isn't a filter on the terms to aggregate. I had removed that specialization in elastic#57241 which resulted in some slow down as well. This adds it back but in a more clear way. And, hopefully, a way that is marginally faster when there *is* a filter. Closes elastic#57407
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When the `terms` agg runs against strings and uses global ordinals it has an optimization when it collects segments that only ever have a single value for the particular string. This is *very* common. But I broke it in #57241. This fixes that optimization and adds `debug` information that you can use to see how often we collect segments of each type. And adds a test to make sure that I don't break the optimization again. We also had a specialiation for when there isn't a filter on the terms to aggregate. I had removed that specialization in #57241 which resulted in some slow down as well. This adds it back but in a more clear way. And, hopefully, a way that is marginally faster when there *is* a filter. Closes #57407
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When the
termsagg runs against strings and uses global ordinals ithas an optimization when it collects segments that only ever have a
single value for the particular string. This is very common. But I
broke it in #57241. This fixes that optimization and adds
debuginformation that you can use to see how often we collect segments of
each type. And adds a test to make sure that I don't break the
optimization again.
We also had a specialiation for when there isn't a filter on the terms
to aggregate. I had removed that specialization in #57241 which resulted
in some slow down as well. This adds it back but in a more clear way.
And, hopefully, a way that is marginally faster when there is a
filter.
Closes #57407