Re: CLOG contention

On Thu, Jan 5, 2012 at 7:12 PM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
> On Thu, Jan 5, 2012 at 11:10 AM, Simon Riggs <simon(at)2ndquadrant(dot)com> wrote:
>> Let's commit the change to 32.
>
> I would like to do that, but I think we need to at least figure out a
> way to provide an escape hatch for people without much shared memory.
> We could do that, perhaps, by using a formula like this:
>
> 1 CLOG buffer per 128MB of shared_buffers, with a minimum of 8 and a
> maximum of 32

We're talking about an extra 192KB or thereabouts and Clog buffers
will only be the size of subtrans when we've finished.

If you want to have a special low-memory option, then it would need to
include many more things than clog buffers.

Let's just use a constant value for clog buffers until the low-memory
patch arrives.

--
 Simon Riggs                   http://www.2ndQuadrant.com/
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