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| author | Robert Haas <rhaas@postgresql.org> | 2017-03-08 12:05:43 -0500 |
|---|---|---|
| committer | Robert Haas <rhaas@postgresql.org> | 2017-03-08 12:05:43 -0500 |
| commit | f35742ccb7aa53ee3ed8416bbb378b0c3eeb6bb9 (patch) | |
| tree | 66c88951dd3b1546159869072e8ff3e3b506568b /src/backend/access/heap/heapam.c | |
| parent | 4eafdcc27608dfb8a3afa3155d6ae07f66179782 (diff) | |
| download | postgresql-f35742ccb7aa53ee3ed8416bbb378b0c3eeb6bb9.tar.gz postgresql-f35742ccb7aa53ee3ed8416bbb378b0c3eeb6bb9.zip | |
Support parallel bitmap heap scans.
The index is scanned by a single process, but then all cooperating
processes can iterate jointly over the resulting set of heap blocks.
In the future, we might also want to support using a parallel bitmap
index scan to set up for a parallel bitmap heap scan, but that's a
job for another day.
Dilip Kumar, with some corrections and cosmetic changes by me. The
larger patch set of which this is a part has been reviewed and tested
by (at least) Andres Freund, Amit Khandekar, Tushar Ahuja, Rafia
Sabih, Haribabu Kommi, Thomas Munro, and me.
Discussion: http://postgr.es/m/CAFiTN-uc4=0WxRGfCzs-xfkMYcSEWUC-Fon6thkJGjkh9i=13A@mail.gmail.com
Diffstat (limited to 'src/backend/access/heap/heapam.c')
| -rw-r--r-- | src/backend/access/heap/heapam.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c index af258366a20..bffc971d689 100644 --- a/src/backend/access/heap/heapam.c +++ b/src/backend/access/heap/heapam.c @@ -1754,6 +1754,22 @@ retry: } /* ---------------- + * heap_update_snapshot + * + * Update snapshot info in heap scan descriptor. + * ---------------- + */ +void +heap_update_snapshot(HeapScanDesc scan, Snapshot snapshot) +{ + Assert(IsMVCCSnapshot(snapshot)); + + RegisterSnapshot(snapshot); + scan->rs_snapshot = snapshot; + scan->rs_temp_snap = true; +} + +/* ---------------- * heap_getnext - retrieve next tuple in scan * * Fix to work with index relations. |