Re: WAL Rate Limiting

On Wed, Jan 15, 2014 at 3:20 AM, Simon Riggs <simon(at)2ndquadrant(dot)com> wrote:

> We've discussed previously the negative impact of large bulk
> operations, especially wrt WAL writes. Patch here allows maintenance
> operations to have their WAL generation slowed down as a replication
> lag prevention feature.
>
> I believe there was originally intended to be some work on I/O rate
> limiting, but that hasn't happened and is in some ways orthogonal to
> this patch and we will likely eventually want both.
>
> Single new parameter works very similarly to vacuum_cost_delay
>
> wal_rate_limit_delay = Xms
>

Seems like a really bad name if we are only slowing down some commands -
that seems to indicate we're slowing down all of them. I think it should be
something that indicates that it only affects the maintenance commands.

--
Magnus Hagander
Me: http://www.hagander.net/
Work: http://www.redpill-linpro.com/