Re: Turn off Hyperthreading! WAS: 60 core performance with 9.3

From: Josh Berkus <josh(at)agliodbs(dot)com>
To: Andres Freund <andres(at)2ndquadrant(dot)com>
Cc: Bruce Momjian <bruce(at)momjian(dot)us>, pgsql-performance(at)postgresql(dot)org, Mark Kirkwood <mark(dot)kirkwood(at)catalyst(dot)net(dot)nz>, "Graeme B(dot) Bell" <grb(at)skogoglandskap(dot)no>
Subject: Re: Turn off Hyperthreading! WAS: 60 core performance with 9.3
Date: 2014-08-25 22:13:59
Message-ID: 53FBB527.9030007@agliodbs.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-performance

On 08/22/2014 07:02 AM, Andres Freund wrote:
> On 2014-08-21 14:02:26 -0700, Josh Berkus wrote:
>> On 08/20/2014 07:40 PM, Bruce Momjian wrote:
>>> Not sure how you can make such a blanket statement when so many people
>>> have tested and shown the benefits of hyper-threading.
>>
>> Actually, I don't know that anyone has posted the benefits of HT.
>> Link?
>
> There's definitely cases where it can help. But it's highly workload
> *and* hardware dependent.

The only cases I've seen where HT can be beneficial is when you have
large numbers of idle connections. Then the idle connections can be
"parked" on the HT virtual cores. However, even in this case I haven't
seen a head-to-head performance comparison.

--
Josh Berkus
PostgreSQL Experts Inc.
http://pgexperts.com

In response to

Responses

Browse pgsql-performance by date

  From Date Subject
Next Message Jeff Janes 2014-08-26 01:51:35 Re: tuning postgresql 9.3.5 and multiple cores
Previous Message Rich 2014-08-25 20:26:57 From: Rich