| From: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
|---|---|
| To: | Andres Freund <andres(at)2ndquadrant(dot)com> |
| Cc: | KONDO Mitsumasa <kondo(dot)mitsumasa(at)lab(dot)ntt(dot)co(dot)jp>, Robert Haas <robertmhaas(at)gmail(dot)com>, Heikki Linnakangas <hlinnakangas(at)vmware(dot)com>, PostgreSQL-development <pgsql-hackers(at)postgresql(dot)org> |
| Subject: | Re: Improvement of checkpoint IO scheduler for stable transaction responses |
| Date: | 2013-07-04 15:21:05 |
| Message-ID: | 21929.1372951265@sss.pgh.pa.us |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers |
Andres Freund <andres(at)2ndquadrant(dot)com> writes:
> I don't like going in this direction at all:
> 1) it breaks pg_upgrade. Which means many of the bigger users won't be
> able to migrate to this and most packagers would carry the old
> segsize around forever.
> Even if we could get pg_upgrade to split files accordingly link mode
> would still be broken.
TBH, I think *any* rearrangement of the on-disk storage files is going
to be rejected. It seems very unlikely to me that you could demonstrate
a checkpoint performance improvement from that that occurs consistently
across different platforms and filesystems. And as Andres points out,
the pain associated with it is going to be bad enough that a very high
bar will be set on whether you've proven the change is worthwhile.
regards, tom lane
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Robert Haas | 2013-07-04 15:32:18 | pgsql: Add new GUC, max_worker_processes, limiting number of bgworkers. |
| Previous Message | Robert Haas | 2013-07-04 15:13:42 | Re: Mention in bgworker docs that db connection needs shmem access |