git@vger.kernel.org mailing list mirror (one of many)
 help / color / mirror / code / Atom feed
From: Jeff King <peff@peff.net>
To: Carlo Arenas <carenas@gmail.com>
Cc: "brian m. carlson" <sandals@crustytoothpaste.net>,
	"Junio C Hamano" <gitster@pobox.com>,
	"Linus Torvalds" <torvalds@linux-foundation.org>,
	"René Scharfe" <l.s.r@web.de>,
	"Han-Wen Nienhuys" <hanwen@google.com>, git <git@vger.kernel.org>,
	"Han-Wen Nienhuys" <hanwenn@gmail.com>
Subject: Re: [PATCH 1/2] bswap.h: drop unaligned loads
Date: Fri, 25 Sep 2020 05:09:06 -0400	[thread overview]
Message-ID: <20200925090906.GA66146@coredump.intra.peff.net> (raw)
In-Reply-To: <CAPUEspjpUeaqCCuBJpQLSTv=C_P4f5h22HoTPm9+9rB7k0NkaQ@mail.gmail.com>

On Fri, Sep 25, 2020 at 02:05:09AM -0700, Carlo Arenas wrote:

> > >   [stock]
> > >   Benchmark #1: t/helper/test-tool sha1 <foo.rand
> > >     Time (mean ± σ):      6.638 s ±  0.081 s    [User: 6.269 s, System: 0.368 s]
> > >     Range (min … max):    6.550 s …  6.841 s    10 runs
> 
> slightly offtopic but what generates this nicely formatted output?

It's this:

  https://github.com/sharkdp/hyperfine

It will actually run both versions and compare them, but it's a little
more involved to set up (since you have to do a build step in between).

> > I cannot speak for s390, since I have never owned one
> 
> I happen to be lucky enough to have access to one (RHEL 8.2/z15, gcc
> 8.3.1) and seems (third consecutive run):
> 
> stock: user: 7.555s, system: 1.191s
> -DNO_UNALIGNED_LOADS: user: 7.561s, system: 1.189s

Thanks. That's not too surprising. gcc 8 seems to be able to optimize
both versions to the same thing (though I have no idea if s390 has a
bswap instruction).

-Peff

  reply	other threads:[~2020-09-25  9:09 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-09-24 19:16 [PATCH 0/2] drop unaligned loads Jeff King
2020-09-24 19:21 ` [PATCH 1/2] bswap.h: " Jeff King
2020-09-24 22:02   ` René Scharfe
2020-09-25  4:56     ` Jeff King
2020-09-25  1:13   ` brian m. carlson
2020-09-25  9:05     ` Carlo Arenas
2020-09-25  9:09       ` Jeff King [this message]
2020-09-25 20:48       ` Thomas Guyot
2020-09-24 19:22 ` [PATCH 2/2] Revert "fast-export: use local array to store anonymized oid" Jeff King

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

  List information: http://vger.kernel.org/majordomo-info.html

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200925090906.GA66146@coredump.intra.peff.net \
    --to=peff@peff.net \
    --cc=carenas@gmail.com \
    --cc=git@vger.kernel.org \
    --cc=gitster@pobox.com \
    --cc=hanwen@google.com \
    --cc=hanwenn@gmail.com \
    --cc=l.s.r@web.de \
    --cc=sandals@crustytoothpaste.net \
    --cc=torvalds@linux-foundation.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. 
Code repositories for project(s) associated with this public inbox

	https://80x24.org/mirrors/git.git

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).