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A handful of fixes to codegen memory usage: * Delete the IR module when we're done with it (it can be fairly large) * Track the compiled code size (typically not that large, but it can add up if there are many fragments). * Estimate optimisation memory requirements and track it in the memory tracker. This is very crude but much better than not tracking it. A handful of fixes to improve codegen time/cost, particularly targeted at compute stats workloads: * Avoid over-inlining when there are many aggregate functions, conjuncts, etc by adding "NoInline" attributes. * Don't codegen non-grouping merge aggregations. They will only process one row per Impala daemon, so codegen is not worth it. * Make the Hll algorithm more efficient by specialising the hash function based on decimal width. Limitations: * This doesn't tackle over-inlining of large expr trees, but a similar approach will be used there in a follow-on patch. Perf: Compute stats on functional_parquet.widetable_1000_cols goes from 1min+ of codegen to ~ 5s codegen on my machine. Local perf runs of tpc-h and targeted perf showed no regressions and some moderate improvements (1-2%). Also did an experiment to understand the perf consequences of disabling inlining. I manually set CODEGEN_INLINE_EXPRS_THRESHOLD to 0, and ran: drop stats tpch_20_parquet.lineitem compute stats tpch_20_parquet.lineitem; There was no difference in time spent in the agg node: 30.7s with inlining, 30.5s without. Change-Id: Id10015b49da182cb181a653ac8464b4a18b71091 Reviewed-on: http://gerrit.cloudera.org:8080/4956 Reviewed-by: Tim Armstrong <tarmstrong@cloudera.com> Reviewed-by: Marcel Kornacker <marcel@cloudera.com> Tested-by: Internal Jenkins
This directory contains Impala test workloads. The directory layout for the workloads should follow: workloads/ <data set name>/<data set name>_dimensions.csv <- The test dimension file <data set name>/<data set name>_core.csv <- A test vector file <data set name>/<data set name>_pairwise.csv <data set name>/<data set name>_exhaustive.csv <data set name>/queries/<query test>.test <- The queries for this workload