From: Avi Kivity <avi@scylladb.com>
To: David Smith <dsmith@redhat.com>, "Frank Ch. Eigler" <fche@redhat.com>
Cc: Mark Wielaard <mjw@redhat.com>, systemtap@sourceware.org
Subject: Re: Some newbie questions
Date: Wed, 17 Aug 2016 18:22:00 -0000 [thread overview]
Message-ID: <16163b32-fb65-0eba-3722-b702237657cf@scylladb.com> (raw)
In-Reply-To: <ee0ef821-19cb-b3d6-1982-90eb563c9249@redhat.com>
On 08/17/2016 09:06 PM, David Smith wrote:
> On 08/17/2016 10:15 AM, Avi Kivity wrote:
>
> ... stuff deleted ...
>
>> My load indeed calls epoll_wait() at a high rate, with zero timeout.
>> But now it's completely dominated by tracing overhead.
> I'm not sure how much it will help, but one easy fix would be to replace
> all your '[pid(), tid()]' array indexing with just '[tid()]' array indexing.
>
> Try changing that and see if the tracing overhead goes down a bit.
>
Yeah, I forgot to do that.
But it's really unlikely to help, all the overhead is coming from
syscall tracing, which I didn't ask for.
next prev parent reply other threads:[~2016-08-17 18:22 UTC|newest]
Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-08-07 8:08 Avi Kivity
2016-08-07 9:16 ` Avi Kivity
2016-08-08 14:58 ` David Smith
2016-08-09 6:51 ` Avi Kivity
2016-08-09 13:54 ` Mark Wielaard
2016-08-09 14:11 ` Avi Kivity
2016-08-10 15:33 ` Frank Ch. Eigler
2016-08-10 15:39 ` Avi Kivity
2016-08-10 15:40 ` Avi Kivity
2016-08-10 16:47 ` Frank Ch. Eigler
2016-08-11 7:51 ` Avi Kivity
2016-08-11 8:13 ` Avi Kivity
2016-08-11 16:18 ` Frank Ch. Eigler
2016-08-17 15:15 ` Avi Kivity
2016-08-17 18:06 ` David Smith
2016-08-17 18:22 ` Avi Kivity [this message]
2016-08-17 18:10 ` Frank Ch. Eigler
2016-08-17 18:30 ` Avi Kivity
2016-08-17 18:35 ` Frank Ch. Eigler
2016-08-17 18:42 ` Avi Kivity
2016-08-25 16:21 ` Avi Kivity
2016-08-25 17:37 ` David Smith
2016-08-26 18:39 ` Avi Kivity
2016-08-26 20:08 ` David Smith
2016-08-26 21:21 ` Josh Stone
2016-08-28 13:30 ` Avi Kivity
2016-08-28 13:35 ` Avi Kivity
2016-08-28 13:45 ` Avi Kivity
2016-08-29 18:26 ` David Smith
2016-08-31 16:44 ` Avi Kivity
2016-08-09 15:17 ` David Smith
2016-08-09 15:28 ` Avi Kivity
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