Re: [PATCH] Incremental sort (was: PoC: Partial sort) - Mailing list pgsql-hackers

From Peter Geoghegan
Subject Re: [PATCH] Incremental sort (was: PoC: Partial sort)
Date
Msg-id CAH2-Wz=L8dZNttnvSXvH6NTMWw2T5VsBBC4oU4tLTMV9CoLRvg@mail.gmail.com
Whole thread Raw
In response to Re: [PATCH] Incremental sort (was: PoC: Partial sort)  (James Coleman <jtc331@gmail.com>)
Responses Re: [PATCH] Incremental sort (was: PoC: Partial sort)
List pgsql-hackers
On Tue, Jun 25, 2019 at 11:03 AM James Coleman <jtc331@gmail.com> wrote:
> No, I haven't confirmed that it's called less frequently, and I'd be
> extremely surprised if it were given the diff doesn't suggest any
> changes to that at all.

I must have misunderstood, then. I thought that you were suggesting
that that might have happened.

> If you think it's important enough to do so, I can instrument it to
> confirm, but I was mostly wanting to know if there were any other
> plausible explanations, and I think you've provided one: there *are*
> changes in the patch to memory contexts in tuplesort.c, so if memory
> fragmentation is a real concern this patch could definitely notice
> changes in that regard.

Sounds like it's probably fragmentation. That's generally hard to measure.

-- 
Peter Geoghegan



pgsql-hackers by date:

Previous
From: Andres Freund
Date:
Subject: Don't allocate IndexAmRoutine dynamically?
Next
From: Amit Kapila
Date:
Subject: Re: POC: Cleaning up orphaned files using undo logs