1. + * ioss_PscanLen This is needed for parallel index scan * ---------------- */ typedef struct IndexOnlyScanState @@ -1427,6 +1428,7 @@ typedef struct IndexOnlyScanState IndexScanDesc ioss_ScanDesc; Buffer ioss_VMBuffer; long ioss_HeapFetches; + Size ioss_PscanLen; /* This is needed for parallel index scan */
No need to mention same comment at multiple places. I think you keep it on top of structure. The explanation could be some thing like "size of parallel index only scan descriptor"
Fixed.
2. + node->ioss_ScanDesc->xs_want_itup = true;
I think wherever you are initializing xs_want_itup, you should initialize ioss_VMBuffer as well. Is there a reason for not doing so?
Done.
3. explain (costs off) select sum(parallel_restricted(unique1)) from tenk1 group by(parallel_restricted(unique1)); - QUERY PLAN ----------------------------------------------------- + QUERY PLAN +------------------------------------------------------------------- HashAggregate Group Key: parallel_restricted(unique1) - -> Index Only Scan using tenk1_unique1 on tenk1 -(3 rows) + -> Gather + Workers Planned: 4 + -> Parallel Index Only Scan using tenk1_unique1 on tenk1 +(5 rows)
It doesn't look good that you want to test parallel index only scan for a test case that wants to test restricted function. The comments atop test looks odd. I suggest add a separate test (both explain and actual execution of query) for parallel index only scan as we have for parallel plans for other queries and see if we can keep the output of existing test same.
Agree, but actually the objective of this test-case is met even with this plan. To restrict parallel index-only scan here, modification in query or other parameters would be required. However, for the proper code-coverage and otherwise I have added test-case for parallel index-only scan.
4. ExecReScanIndexOnlyScan(IndexOnlyScanState *node) { .. + /* + * if we are here to just update the scan keys, then don't reset parallel + * scan + */ + if (node->ioss_NumRuntimeKeys != 0 && !node->ioss_RuntimeKeysReady) + reset_parallel_scan = false; .. }
I think here you can update the comment to indicate that for detailed reason refer ExecReScanIndexScan.
Done.
Please find the attached patch for the revised version.
Just an FYI, in my recent tests on TPC-H 300 scale factor, Q16 showed improved execution time from 830 seconds to 730 seconds with this patch when used with parallel merge-join patch [1].
