Re: Backup throttling

2013-08-20 08:37 keltezéssel, Heikki Linnakangas írta:
> On 19.08.2013 21:15, Boszormenyi Zoltan wrote:
>> 2013-08-19 19:20 keltezéssel, Andres Freund írta:
>>> 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.
>
> Throttling in the client seems much better to me. TCP is designed to handle a slow client.
>
>> Maybe throttling the walsender is not a good idea, it can lead
>> to DoS via disk space shortage.
>
> If a client can initiate a backup and/or streaming replication, he can already do much 
> more damage than a DoS via out of disk space. And a nothing stops even a non-privileged 
> user from causing an out of disk space situation anyway. IOW that's a non-issue.

I got to the same conclusion this morning, but because of wal_keep_segments.

Best regards,
Zoltán Böszörményi

>
> - Heikki
>
>


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Zoltán Böszörményi
Cybertec Schönig & Schönig GmbH
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