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Re: [HACKERS] Block level parallel vacuum - Mailing list pgsql-hackers

From Haribabu Kommi
Subject Re: [HACKERS] Block level parallel vacuum
Date
Msg-id CAJrrPGfpb=-4xE2t1OApnWnu5qL=Rianqz85PE_pX4Lts0QBeg@mail.gmail.com
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In response to Re: [HACKERS] Block level parallel vacuum  (Masahiko Sawada <sawada.mshk@gmail.com>)
Responses Re: [HACKERS] Block level parallel vacuum
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On Thu, Feb 14, 2019 at 9:17 PM Masahiko Sawada <sawada.mshk@gmail.com> wrote:
Thank you. Attached the rebased patch.

I ran some performance tests to compare the parallelism benefits,
but I got some strange results of performance overhead, may be it is
because, I tested it on my laptop.

FYI,

Table schema:

create table tbl(f1 int, f2 char(100), f3 float4, f4 char(100), f5 float8, f6 char(100), f7 bigint);


Tbl with 3 indexes

1000 record deletion
master - 22ms
patch - 25ms with 0 parallel workers
patch - 43ms with 1 parallel worker
patch - 72ms with 2 parallel workers


10000 record deletion
master - 52ms
patch - 56ms with 0 parallel workers
patch - 79ms with 1 parallel worker
patch - 86ms with 2 parallel workers


100000 record deletion
master - 410ms
patch - 379ms with 0 parallel workers
patch - 330ms with 1 parallel worker
patch - 289ms with 2 parallel workers


Tbl with 5 indexes

1000 record deletion
master - 28ms
patch - 34ms with 0 parallel workers
patch - 86ms with 2 parallel workers
patch - 106ms with 4 parallel workers


10000 record deletion
master - 58ms
patch - 63ms with 0 parallel workers
patch - 101ms with 2 parallel workers
patch - 118ms with 4 parallel workers


100000 record deletion
master - 632ms
patch - 490ms with 0 parallel workers
patch - 455ms with 2 parallel workers
patch - 403ms with 4 parallel workers



Tbl with 7 indexes

1000 record deletion
master - 35ms
patch - 44ms with 0 parallel workers
patch - 93ms with 2 parallel workers
patch - 110ms with 4 parallel workers
patch - 123ms with 6 parallel workers

10000 record deletion
master - 76ms
patch - 78ms with 0 parallel workers
patch - 135ms with 2 parallel workers
patch - 143ms with 4 parallel workers
patch - 139ms with 6 parallel workers

100000 record deletion
master - 641ms
patch - 656ms with 0 parallel workers
patch - 613ms with 2 parallel workers
patch - 735ms with 4 parallel workers
patch - 679ms with 6 parallel workers


Regards,
Haribabu Kommi
Fujitsu Australia

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