From: Ryan Arnold <rsa@us.ibm.com>
To: Segher Boessenkool <segher@kernel.crashing.org>
Cc: Will Schmidt <will_schmidt@vnet.ibm.com>,
Steven Munroe <sjmunroe@us.ibm.com>,
linuxppc-dev@ozlabs.org
Subject: Re: [RFC] Moving toward smarter disabling of FPRs, VRs, and VSRs in the MSR
Date: Sat, 14 Mar 2009 09:58:59 -0500 [thread overview]
Message-ID: <1237042739.8874.3.camel@localhost.localdomain> (raw)
In-Reply-To: <FFBC9638-D064-43F9-B764-243739289710@kernel.crashing.org>
On Sat, 2009-03-14 at 14:49 +0100, Segher Boessenkool wrote:
> > Another option might be simply to say that if an app has used FP,
> > VMX or
> > VSX -once-, then it's likely to do it again and just keep re-enabling
> > it :-)
> >
> > I'm serious here, do we know that many cases where these things are
> > used
> > seldomly once in a while ?
>
> For FP, I believe many apps use it only sporadically. But for VMX
> and VSX,
> yeah, it might well be optimal to keep it enabled all the time. Someone
> should do some profiling...
We can do some VMX testing on existing POWER6 machines. The VSX
instruction set hasn't been fully implemented in GCC yet so we'll need
to wait a bit for that. Does anyone have an idea for a good VMX/Altivec
benchmark?
Ryan
next prev parent reply other threads:[~2009-03-14 14:59 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-03-13 20:23 [RFC] Moving toward smarter disabling of FPRs, VRs, and VSRs in the MSR Ryan Arnold
2009-03-13 21:15 ` Kumar Gala
2009-03-13 22:45 ` Benjamin Herrenschmidt
2009-03-13 23:52 ` Josh Boyer
2009-03-14 2:31 ` Ryan Arnold
2009-03-14 3:22 ` Benjamin Herrenschmidt
2009-03-14 13:55 ` Segher Boessenkool
2009-03-14 13:49 ` Segher Boessenkool
2009-03-14 14:58 ` Ryan Arnold [this message]
2009-03-16 0:49 ` Benjamin Herrenschmidt
2009-03-16 6:43 ` Michael Neuling
2009-03-16 10:52 ` Gabriel Paubert
2009-03-14 8:20 ` Michael Neuling
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1237042739.8874.3.camel@localhost.localdomain \
--to=rsa@us.ibm.com \
--cc=linuxppc-dev@ozlabs.org \
--cc=segher@kernel.crashing.org \
--cc=sjmunroe@us.ibm.com \
--cc=will_schmidt@vnet.ibm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.