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| author | Tomas Vondra <tomas.vondra@postgresql.org> | 2020-04-07 18:03:24 +0200 |
|---|---|---|
| committer | Tomas Vondra <tomas.vondra@postgresql.org> | 2020-04-07 18:25:13 +0200 |
| commit | d22782a5392f6a1cb6cfca34031b93eb9dd2aa03 (patch) | |
| tree | d49831da8514cd1aa83b076232c3d4c499d52ff8 /src/backend/commands/explain.c | |
| parent | 4bd0ad9e44be9fbc3ad77747d7672dab1c3df7d9 (diff) | |
| download | postgresql-d22782a5392f6a1cb6cfca34031b93eb9dd2aa03.tar.gz postgresql-d22782a5392f6a1cb6cfca34031b93eb9dd2aa03.zip | |
Minor improvements in Incremental Sort explain
Some places still used "Maximum" instead of "Peak" when displaying info
about sort space, so fix that. Also, add a comment clarifying why it's
correct to check the number of full/prefix sort groups.
Author: James Coleman
Discussion: https://postgr.es/m/CAPpHfds1waRZ=NOmueYq0sx1ZSCnt+5QJvizT8ndT2=etZEeAQ@mail.gmail.com
Diffstat (limited to 'src/backend/commands/explain.c')
| -rw-r--r-- | src/backend/commands/explain.c | 20 |
1 files changed, 18 insertions, 2 deletions
diff --git a/src/backend/commands/explain.c b/src/backend/commands/explain.c index baaa5817af7..455f54ef83f 100644 --- a/src/backend/commands/explain.c +++ b/src/backend/commands/explain.c @@ -2841,7 +2841,7 @@ show_incremental_sort_group_info(IncrementalSortGroupInfo *groupInfo, ExplainOpenGroup("Sort Space", memoryName.data, true, es); ExplainPropertyInteger("Average Sort Space Used", "kB", avgSpace, es); - ExplainPropertyInteger("Maximum Sort Space Used", "kB", + ExplainPropertyInteger("Peak Sort Space Used", "kB", groupInfo->maxMemorySpaceUsed, es); ExplainCloseGroup("Sort Spaces", memoryName.data, true, es); @@ -2858,7 +2858,7 @@ show_incremental_sort_group_info(IncrementalSortGroupInfo *groupInfo, ExplainOpenGroup("Sort Space", diskName.data, true, es); ExplainPropertyInteger("Average Sort Space Used", "kB", avgSpace, es); - ExplainPropertyInteger("Maximum Sort Space Used", "kB", + ExplainPropertyInteger("Peak Sort Space Used", "kB", groupInfo->maxDiskSpaceUsed, es); ExplainCloseGroup("Sort Spaces", diskName.data, true, es); @@ -2883,6 +2883,15 @@ show_incremental_sort_info(IncrementalSortState *incrsortstate, if (!es->analyze) return; + /* + * Since we never have any prefix groups unless we've first sorted a full + * groups and transitioned modes (copying the tuples into a prefix group), + * we don't need to do anything if there were 0 full groups. + * + * We still have to continue after this block if there are no full groups, + * though, since it's possible that we have workers that did real work even + * if the leader didn't participate. + */ if (fullsortGroupInfo->groupCount > 0) { show_incremental_sort_group_info(fullsortGroupInfo, "Full-sort", true, es); @@ -2914,6 +2923,13 @@ show_incremental_sort_info(IncrementalSortState *incrsortstate, */ fullsortGroupInfo = &incsort_info->fullsortGroupInfo; prefixsortGroupInfo = &incsort_info->prefixsortGroupInfo; + + /* + * Since we never have any prefix groups unless we've first sorted + * a full groups and transitioned modes (copying the tuples into a + * prefix group), we don't need to do anything if there were 0 full + * groups. + */ if (fullsortGroupInfo->groupCount == 0 && prefixsortGroupInfo->groupCount == 0) continue; |