Re: Backup throttling

Andres Freund <andres@2ndquadrant.com>

From: Andres Freund <andres@2ndquadrant.com>
To: Boszormenyi Zoltan <zb@cybertec.at>
Cc: Antonin Houska <antonin.houska@gmail.com>, pgsql-hackers@postgresql.org
Date: 2013-08-19T19:11:00Z
Lists: pgsql-hackers
On 2013-08-19 20:15:51 +0200, Boszormenyi Zoltan wrote:
> 2013-08-19 19:20 keltezéssel, Andres Freund írta:
> >Hi,
> >
> >On 2013-07-24 09:20:52 +0200, Antonin Houska wrote:
> >>Hello,
> >>the purpose of this patch is to limit impact of pg_backup on running server.
> >>Feedback is appreciated.
> >Based on a quick look it seems like you're throttling on the receiving
> >side. Is that a good idea? Especially over longer latency links, TCP
> >buffering will reduce the effect on the sender side considerably.

> Throttling on the sender side requires extending the syntax of
> BASE_BACKUP and maybe START_REPLICATION so both can be
> throttled but throttling is still initiated by the receiver side.

Seems fine to me. Under the premise that the idea is decided to be
worthwile to be integrated. Which I am not yet convinced of.

> Maybe throttling the walsender is not a good idea, it can lead
> to DoS via disk space shortage.

Not in a measurably different way than receiver side throttling?

Greetings,

Andres Freund

-- 
 Andres Freund	                   http://www.2ndQuadrant.com/
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