Re: autovacuum multiworkers, patch 5

From: ITAGAKI Takahiro <itagaki(dot)takahiro(at)oss(dot)ntt(dot)co(dot)jp>
To: Alvaro Herrera <alvherre(at)commandprompt(dot)com>, pgsql-patches(at)postgresql(dot)org
Subject: Re: autovacuum multiworkers, patch 5
Date: 2007-04-09 11:01:34
Message-ID: 20070409193116.879A.ITAGAKI.TAKAHIRO@oss.ntt.co.jp
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers pgsql-patches

> > >Yes, that's correct. Per previous discussion, what I actually wanted to
> > >do was to create a GUC setting to simplify the whole thing, something
> > >like "autovacuum_max_mb_per_second" or "autovacuum_max_io_per_second".
> > >Then, have each worker use up to (max_per_second/active workers) as much
> > >IO resources.
>
> One thing I forgot to mention is that this is unlikely to be implemented
> in 8.3.

This is a WIP cost balancing patch built on autovacuum-multiworkers-5.patch.
The total cost of workers are adjusted to autovacuum_vacuum_cost_delay.

I added copy of worker's cost parameters to the shared WorkerInfo array.
A launcher and each worker reads and writes the copied parameters when
a worker starts a vacuum job or exit the process. Workers assign their local
VacuumCostDelay from the shared value every sleep in vacuum_delay_point().

I agree that "mb_per_second" or "io_per_second" are easier to use than
present cost delay parameters, but we need more research to move to it.
I think it is better to keep "cost_limit" and "cost_delay" as of 8.3,
but we need cost-balanced multiworkers at any rate.

Regards,
---
ITAGAKI Takahiro
NTT Open Source Software Center

Attachment Content-Type Size
autovacuum_balance.patch application/octet-stream 11.1 KB

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Alvaro Herrera 2007-04-09 13:40:00 Re: autovacuum multiworkers, patch 5
Previous Message Simon Riggs 2007-04-09 06:21:57 Re: Reviewers Guide to DeferredTransactions/TransactionGuarantee

Browse pgsql-patches by date

  From Date Subject
Next Message Hiroshi Saito 2007-04-09 13:21:30 Re: Clear up strxfrm() in UTF-8 with locale on Windows
Previous Message ITAGAKI Takahiro 2007-04-09 09:22:12 Clear up strxfrm() in UTF-8 with locale on Windows