| From: | Robert Haas <robertmhaas(at)gmail(dot)com> |
|---|---|
| To: | Alexander Korotkov <a(dot)korotkov(at)postgrespro(dot)ru> |
| Cc: | pgsql-hackers <pgsql-hackers(at)postgresql(dot)org> |
| Subject: | Re: Should we cacheline align PGXACT? |
| Date: | 2016-08-20 18:33:13 |
| Message-ID: | 7503E425-6651-4D40-83FD-592AF580D618@gmail.com |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers |
On Aug 19, 2016, at 2:12 AM, Alexander Korotkov <a(dot)korotkov(at)postgrespro(dot)ru> wrote:
> Hackers,
>
> originally this idea was proposed by Andres Freund while experimenting with lockfree Pin/UnpinBuffer [1].
> The patch is attached as well as results of pgbench -S on 72-cores machine. As before it shows huge benefit in this case.
> For sure, we should validate that it doesn't cause performance regression in other cases. At least we should test read-write and smaller machines.
> Any other ideas?
Wow, nice results. My intuition on why PGXACT helped in the first place was that it minimized the number of cache lines that had to be touched to take a snapshot. Padding obviously would somewhat increase that again, so I can't quite understand why it seems to be helping... any idea?
...Robert
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Tom Lane | 2016-08-20 18:38:52 | Re: Should we cacheline align PGXACT? |
| Previous Message | Tom Lane | 2016-08-20 18:02:30 | Re: Patch: initdb: "'" for QUOTE_PATH (non-windows) |