Re: Backup throttling

2013-08-19 21:11 keltezéssel, Andres Freund írta:
> 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?

No, but that's not what I meant.

START_BACKUP has to deal with big data but it finishes after some time.
But pg_receivexlog may sit there indefinitely...

Best regards,
Zoltán Böszörményi

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Zoltán Böszörményi
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