On 2014-02-04 16:24:02 -0800, Peter Geoghegan wrote:
On Mon, Feb 3, 2014 at 3:38 PM, Andres Freund and...@2ndquadrant.com wrote:
A quick hack (attached) making BufferDescriptor 64byte aligned indeed
restored performance across all max_connections settings. It's not
surprising that a
Andres Freund and...@2ndquadrant.com writes:
On 2014-02-04 16:24:02 -0800, Peter Geoghegan wrote:
I suspect that the scenario described in this article accounts for the
quite noticeable effect reported: http://danluu.com/3c-conflict
I don't think that's applicable here.
Maybe, or maybe not,
On 2014-02-05 09:57:11 -0500, Tom Lane wrote:
Andres Freund and...@2ndquadrant.com writes:
On 2014-02-04 16:24:02 -0800, Peter Geoghegan wrote:
I suspect that the scenario described in this article accounts for the
quite noticeable effect reported: http://danluu.com/3c-conflict
I don't
On Wed, Feb 5, 2014 at 3:57 PM, Tom Lane t...@sss.pgh.pa.us wrote:
Maybe, or maybe not, but I think it does say that we should be very wary
of proposals to force data structure alignment without any testing of the
consequences.
Sure. see for instance
On 2014-02-05 16:14:01 +0100, Greg Stark wrote:
I see a lot of confusion online over whether cache lines
are 64 bytes, 128 bytes, or other length even just on Intel
architectures, let alone others.
All current x86 processors use 64. But even if it were bigger/smaller,
they will be either 32,
On Wed, Feb 5, 2014 at 7:21 AM, Andres Freund and...@2ndquadrant.com wrote:
All current x86 processors use 64. But even if it were bigger/smaller,
they will be either 32, or 128. Neither benefits from touching more
cachelines than necessary. E.g. in the 128 case, we could still touch
two with
On Tue, Feb 4, 2014 at 4:24 PM, Peter Geoghegan p...@heroku.com wrote:
There is something you have not drawn explicit attention to that is
very interesting. If we take REL9_3_STABLE tip to be representative
(built with full -O2 optimization, no assertions just debugging
symbols), setting
On 2014-02-04 00:38:19 +0100, Andres Freund wrote:
A quick hack (attached) making BufferDescriptor 64byte aligned indeed
restored performance across all max_connections settings. It's not
surprising that a misaligned buffer descriptor causes problems -
there'll be plenty of false
On Tue, Feb 4, 2014 at 4:21 AM, Andres Freund and...@2ndquadrant.com wrote:
Which imo means fixing this got more important...
I strongly agree.
--
Peter Geoghegan
--
Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org)
To make changes to your subscription:
On Mon, Feb 3, 2014 at 3:38 PM, Andres Freund and...@2ndquadrant.com wrote:
A quick hack (attached) making BufferDescriptor 64byte aligned indeed
restored performance across all max_connections settings. It's not
surprising that a misaligned buffer descriptor causes problems -
there'll be
On Sun, Feb 2, 2014 at 7:13 AM, Andres Freund and...@2ndquadrant.com wrote:
Just as reference, we're talking about a performance degradation from
475963.613865 tps to 197744.913556 in a pgbench -S -cj64 just by setting
max_connections to 90, from 91...
That's pretty terrible.
So, I looked
On 2014-02-03 15:17:13 -0800, Peter Geoghegan wrote:
On Sun, Feb 2, 2014 at 7:13 AM, Andres Freund and...@2ndquadrant.com wrote:
Just as reference, we're talking about a performance degradation from
475963.613865 tps to 197744.913556 in a pgbench -S -cj64 just by setting
max_connections to
12 matches
Mail list logo
