Re: Reduce pinning in btree indexes

On 4 March 2015 at 03:16, Kevin Grittner <kgrittn(at)ymail(dot)com> wrote:

> How do people feel about the idea of me pushing this for 9.5 (after
> I clean up all the affected comments and README files)? I know
> this first appeared in the last CF, but the footprint is fairly
> small and the only user-visible behavior change is that a btree
> index scan of a WAL-logged table using an MVCC snapshot no longer
> blocks a vacuum indefinitely. (If there are objections I will move
> this to the first CF for the next release.)

It helps Hot Standby also, BTW. I proposed this previously, but it was
shot down, so I'm glad to see it happening.

I'm not sure why you have proposed only half the solution though?
Hopefully we aren't just submitting the difficult half that you needed
feedback on? Let's see the whole "snapshot too old" patch as well,
since that affects core PostgresSQL also.

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