From: Igor Mammedov <imammedo@redhat.com>
To: Richard Henderson <richard.henderson@linaro.org>
Cc: "Alex Bennée" <alex.bennee@linaro.org>,
"Paolo Bonzini" <pbonzini@redhat.com>,
qemu-arm@nongnu.org, qemu-devel@nongnu.org,
"Laurent Vivier" <laurent@vivier.eu>
Subject: Re: [PATCH v1 4/4] accel/tcg: increase default code gen buffer size for 64 bit
Date: Thu, 27 Feb 2020 15:13:13 +0100 [thread overview]
Message-ID: <20200227151313.7b2f188b@redhat.com> (raw)
In-Reply-To: <56f5e355-9357-e212-e92b-9db1d8424dea@linaro.org>
On Thu, 27 Feb 2020 04:56:46 -0800
Richard Henderson <richard.henderson@linaro.org> wrote:
> On 2/27/20 4:31 AM, Alex Bennée wrote:
> >> It does not make sense for a linux-user chroot, running make -jN, on just about
> >> any host. For linux-user, I could be happy with a modest increase, but not all
> >> the way out to 2GiB.
> >>
> >> Discuss.
> >
> > Does it matter that much? Surely for small programs the kernel just
> > never pages in the used portions of the mmap?
>
> That's why I used the example of a build under the chroot, because the compiler
> is not a small program.
>
> Consider when the memory *is* used, and N * 2GB implies lots of paging, where
> the previous N * 32MB did not.
>
> I'm saying that we should consider a setting more like 128MB or so, since the
> value cannot be changed from the command-line, or through the environment.
That's what BSD guys force tb-size to, to speed up system emulation.
>
>
> r~
>
WARNING: multiple messages have this Message-ID (diff)
From: Igor Mammedov <imammedo@redhat.com>
To: Richard Henderson <richard.henderson@linaro.org>
Cc: "Paolo Bonzini" <pbonzini@redhat.com>,
qemu-arm@nongnu.org, "Alex Bennée" <alex.bennee@linaro.org>,
qemu-devel@nongnu.org, "Laurent Vivier" <laurent@vivier.eu>
Subject: Re: [PATCH v1 4/4] accel/tcg: increase default code gen buffer size for 64 bit
Date: Thu, 27 Feb 2020 15:13:13 +0100 [thread overview]
Message-ID: <20200227151313.7b2f188b@redhat.com> (raw)
In-Reply-To: <56f5e355-9357-e212-e92b-9db1d8424dea@linaro.org>
On Thu, 27 Feb 2020 04:56:46 -0800
Richard Henderson <richard.henderson@linaro.org> wrote:
> On 2/27/20 4:31 AM, Alex Bennée wrote:
> >> It does not make sense for a linux-user chroot, running make -jN, on just about
> >> any host. For linux-user, I could be happy with a modest increase, but not all
> >> the way out to 2GiB.
> >>
> >> Discuss.
> >
> > Does it matter that much? Surely for small programs the kernel just
> > never pages in the used portions of the mmap?
>
> That's why I used the example of a build under the chroot, because the compiler
> is not a small program.
>
> Consider when the memory *is* used, and N * 2GB implies lots of paging, where
> the previous N * 32MB did not.
>
> I'm saying that we should consider a setting more like 128MB or so, since the
> value cannot be changed from the command-line, or through the environment.
That's what BSD guys force tb-size to, to speed up system emulation.
>
>
> r~
>
next prev parent reply other threads:[~2020-02-27 14:13 UTC|newest]
Thread overview: 46+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-26 18:10 [PATCH v1 0/4] Fix codegen translation cache size Alex Bennée
2020-02-26 18:10 ` [PATCH v1 1/4] accel/tcg: use units.h for defining code gen buffer sizes Alex Bennée
2020-02-26 18:10 ` Alex Bennée
2020-02-26 22:00 ` Niek Linnenbank
2020-02-26 22:00 ` Niek Linnenbank
2020-02-26 22:49 ` Richard Henderson
2020-02-27 10:54 ` Philippe Mathieu-Daudé
2020-02-26 18:10 ` [PATCH v1 2/4] accel/tcg: remove link between guest ram and TCG cache size Alex Bennée
2020-02-26 18:10 ` Alex Bennée
2020-02-26 22:26 ` Niek Linnenbank
2020-02-26 22:26 ` Niek Linnenbank
2020-02-26 22:50 ` Richard Henderson
2020-02-26 22:50 ` Richard Henderson
2020-02-26 22:49 ` Richard Henderson
2020-02-26 22:49 ` Richard Henderson
2020-02-27 10:58 ` Philippe Mathieu-Daudé
2020-02-27 10:58 ` Philippe Mathieu-Daudé
2020-02-26 18:10 ` [PATCH v1 3/4] accel/tcg: only USE_STATIC_CODE_GEN_BUFFER on 32 bit hosts Alex Bennée
2020-02-26 18:10 ` Alex Bennée
2020-02-26 22:50 ` Richard Henderson
2020-02-27 10:55 ` Philippe Mathieu-Daudé
2020-02-27 19:20 ` Niek Linnenbank
2020-02-27 19:20 ` Niek Linnenbank
2020-02-26 18:10 ` [PATCH v1 4/4] accel/tcg: increase default code gen buffer size for 64 bit Alex Bennée
2020-02-26 18:10 ` Alex Bennée
2020-02-26 22:45 ` Niek Linnenbank
2020-02-26 22:45 ` Niek Linnenbank
2020-02-27 12:19 ` Alex Bennée
2020-02-27 12:19 ` Alex Bennée
2020-02-27 19:01 ` Niek Linnenbank
2020-02-27 19:01 ` Niek Linnenbank
2020-02-26 22:55 ` Richard Henderson
2020-02-27 12:31 ` Alex Bennée
2020-02-27 12:31 ` Alex Bennée
2020-02-27 12:56 ` Richard Henderson
2020-02-27 12:56 ` Richard Henderson
2020-02-27 14:13 ` Igor Mammedov [this message]
2020-02-27 14:13 ` Igor Mammedov
2020-02-27 19:07 ` Niek Linnenbank
2020-02-27 19:07 ` Niek Linnenbank
2020-02-28 7:47 ` Igor Mammedov
2020-02-28 7:47 ` Igor Mammedov
2020-02-28 19:20 ` Alex Bennée
2020-02-28 19:20 ` Alex Bennée
2020-02-28 7:54 ` [PATCH] " Alex Bennée
2020-02-28 7:54 ` Alex Bennée
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=20200227151313.7b2f188b@redhat.com \
--to=imammedo@redhat.com \
--cc=alex.bennee@linaro.org \
--cc=laurent@vivier.eu \
--cc=pbonzini@redhat.com \
--cc=qemu-arm@nongnu.org \
--cc=qemu-devel@nongnu.org \
--cc=richard.henderson@linaro.org \
/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.