RE: [PATCH] Speedup truncates of relation forks

From: "Jamison, Kirk" <k(dot)jamison(at)jp(dot)fujitsu(dot)com>
To: "Jamison, Kirk" <k(dot)jamison(at)jp(dot)fujitsu(dot)com>, 'Thomas Munro' <thomas(dot)munro(at)gmail(dot)com>
Cc: Masahiko Sawada <sawada(dot)mshk(at)gmail(dot)com>, "Tsunakawa, Takayuki" <tsunakawa(dot)takay(at)jp(dot)fujitsu(dot)com>, Tomas Vondra <tomas(dot)vondra(at)2ndquadrant(dot)com>, "pgsql-hackers(at)postgresql(dot)org" <pgsql-hackers(at)postgresql(dot)org>, Adrien Nayrat <adrien(dot)nayrat(at)anayrat(dot)info>
Subject: RE: [PATCH] Speedup truncates of relation forks
Date: 2019-07-24 00:58:24
Message-ID: D09B13F772D2274BB348A310EE3027C65147DC@g01jpexmbkw24
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I repeated the recovery performance test before, and found out that I made a
wrong measurement.
Using the same steps indicated in the previous email (24GB shared_buffers for my case),
the recovery time still significantly improved compared to head
from "13 minutes" to "4 minutes 44 seconds" //not 30 seconds.
It's expected because the measurement of vacuum execution time (no failover)
which I reported in the first email is about the same (although 5 minutes):
> HEAD results
> 3) 24GB shared_buffers = 14 min 13.598 s
> PATCH results
> 3) 24GB shared_buffers = 5 min 35.848 s

Reattaching the patch here again. The V5 of the patch fixed the compile error
mentioned before and mainly addressed the comments/advice of Sawada-san.
- updated more accurate comments describing only current behavior, not history
- updated function name: visibilitymap_truncate_prepare()
- moved the setting of values for smgr_{fsm,vm}_nblocks inside the smgrtruncate()

I'd be grateful if anyone could provide comments, advice, or insights.
Thank you again in advance.

Kirk Jamison

Attachment Content-Type Size
v5-0001-Speedup-truncates-of-relation-forks.patch application/octet-stream 22.7 KB

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