| From: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
|---|---|
| To: | Alvaro Herrera <alvherre(at)2ndquadrant(dot)com> |
| Cc: | Amit Kapila <amit(dot)kapila16(at)gmail(dot)com>, Robert Haas <robertmhaas(at)gmail(dot)com>, Mithun Cy <mithun(dot)cy(at)enterprisedb(dot)com>, pgsql-hackers <pgsql-hackers(at)postgresql(dot)org> |
| Subject: | Re: Possible performance regression in version 10.1 with pgbench read-write tests. |
| Date: | 2018-07-19 19:56:41 |
| Message-ID: | 23412.1532030201@sss.pgh.pa.us |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers |
Alvaro Herrera <alvherre(at)2ndquadrant(dot)com> writes:
> On 2018-Jul-19, Amit Kapila wrote:
>> It appears so. I think we should do something about it as the
>> regression is quite noticeable.
It's not *that* noticeable, as I failed to demonstrate any performance
difference before committing the patch. I think some more investigation
is warranted to find out why some other people are getting different
results.
> So the fix is just to revert the change for the linux makefile? Sounds
> easy enough, code-wise. Do we need more evidence that it's harmful?
Some fraction of 3d21f08bc would also need to be undone. It's also worth
contemplating that we'd be re-introducing old problems with not-enough-
SysV-semaphores, so even if there is a performance benefit to be had,
it's very far from being free.
regards, tom lane
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Nico Williams | 2018-07-19 20:01:44 | Re: [HACKERS] possible self-deadlock window after bad ProcessStartupPacket |
| Previous Message | Nico Williams | 2018-07-19 19:54:52 | Re: [HACKERS] possible self-deadlock window after bad ProcessStartupPacket |