Re: Backup throttling

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.

- Heikki