Add new GUC gp_max_scan_on_shmem which replaced MAX_SCAN_ON_SHMEM#433
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red1452
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RekGRpth
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Nov 25, 2022
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I've checked all the places where new GUC was added and it seems all is correct. The one thing I can suggest is to extend existed regression test (src/test/regress/sql/instr_in_shmem.sql) and test new GUC like it's done for GP_INSTRUMENT_SHMEM_SIZE. |
maksm90
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Won't this GUC conflict with overall limit of shared memory for instrumentation objects gp_instrument_shmem_size? I.e. are we able allocate more intrumentations for SeqScan nodes in shared memory than shmem is available at all?
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It repalced the hard-coded define MAX_SCAN_ON_SHMEM. Specifies the limit of maximum scan node's instrumentations per query in shmem. If table has many partitions, Postgres planner will generate a plan with many SCAN nodes under a APPEND node. If the number of partitions are too many, this plan will occupy too many slots. Here is a limitation on number of shmem slots used by scan nodes for each backend. Instruments exceeding the limitation are allocated in local memory.
RekGRpth
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Stolb27
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This was referenced Jan 26, 2023
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It repalced the hard-coded define MAX_SCAN_ON_SHMEM. Specifies the limit of maximum scan node's instrumentations per query in shmem. If table has many partitions, Postgres planner will generate a plan with many SCAN nodes under a APPEND node. If the number of partitions are too many, this plan will occupy too many slots. Here is a limitation on number of shmem slots used by scan nodes for each backend. Instruments exceeding the limitation are allocated in local memory. (cherry picked from commit 6425610)
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It repalced the hard-coded define MAX_SCAN_ON_SHMEM. Specifies the limit of maximum scan node's instrumentations per query in shmem. If table has many partitions, Postgres planner will generate a plan with many SCAN nodes under a APPEND node. If the number of partitions are too many, this plan will occupy too many slots. Here is a limitation on number of shmem slots used by scan nodes for each backend. Instruments exceeding the limitation are allocated in local memory. (cherry picked from commit 6425610)
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It repalced the hard-coded define MAX_SCAN_ON_SHMEM. Specifies the limit of maximum scan node's instrumentations per query in shmem. If table has many partitions, Postgres planner will generate a plan with many SCAN nodes under a APPEND node. If the number of partitions are too many, this plan will occupy too many slots. Here is a limitation on number of shmem slots used by scan nodes for each backend. Instruments exceeding the limitation are allocated in local memory. (cherry picked from commit 6425610)
KnightMurloc
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It repalced the hard-coded define MAX_SCAN_ON_SHMEM. Specifies the limit of maximum scan node's instrumentations per query in shmem. If table has many partitions, Postgres planner will generate a plan with many SCAN nodes under a APPEND node. If the number of partitions are too many, this plan will occupy too many slots. Here is a limitation on number of shmem slots used by scan nodes for each backend. Instruments exceeding the limitation are allocated in local memory. (cherry picked from commit 6425610)
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New GUC specifies the limit of maximum scan node's instrumentations per query in shmem. If table has many partitions, Postgres planner will generate a plan with many SCAN nodes under a APPEND node. If the number of partitions are too many, this plan will occupy too many slots. Here is a limitation on number of shmem slots used by scan nodes for each backend. Instruments exceeding the limitation are allocated in local memory.
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make installcheck