From: "Ævar Arnfjörð Bjarmason" <avarab@gmail.com>
To: Duy Nguyen <pclouds@gmail.com>
Cc: "Johannes Schindelin" <Johannes.Schindelin@gmx.de>,
"Git Mailing List" <git@vger.kernel.org>,
"SZEDER Gábor" <szeder.dev@gmail.com>,
"Vasco Almeida" <vascomalmeida@sapo.pt>,
"Jiang Xin" <worldhello.net@gmail.com>
Subject: Re: [PATCH] Poison gettext with the Ook language
Date: Tue, 23 Oct 2018 18:45:34 +0200 [thread overview]
Message-ID: <871s8gd32p.fsf@evledraar.gmail.com> (raw)
In-Reply-To: <CACsJy8CX78EbANbv8a354djJaO6dKRpXshHhHJTspJvOSewgpA@mail.gmail.com>
On Tue, Oct 23 2018, Duy Nguyen wrote:
> On Tue, Oct 23, 2018 at 12:17 PM Ævar Arnfjörð Bjarmason
> <avarab@gmail.com> wrote:
>>
>>
>> On Tue, Oct 23 2018, Johannes Schindelin wrote:
>>
>> > Hi Ævar,
>> >
>> > On Mon, 22 Oct 2018, Ævar Arnfjörð Bjarmason wrote:
>> >
>> >> So I think the only reason to keep it [GETTEXT_POISON] compile-time is
>> >> performance, but I don't think that matters. It's not like we're
>> >> printing gigabytes of _() formatted output. Everything where formatting
>> >> matters is plumbing which doesn't use this API. These messages are
>> >> always for human consumption.
>> >
>> > Well, let's make sure that your impression is correct before going too
>> > far. I, too, had the impression that gettext cannot possibly be expensive,
>> > especifally in Git for Windows' settings, where we do not even ship
>> > translations. Yet see the commit message of cc5e1bf99247 (gettext: avoid
>> > initialization if the locale dir is not present, 2018-04-21):
>> >
>> > The runtime of a simple `git.exe version` call on Windows is
>> > currently dominated by the gettext setup, adding a whopping ~150ms
>> > to the ~210ms total.
>> >
>> > I would be in favor of your change to make this a runtime option, of
>> > course, as long as it does not affect performance greatly (in particular
>> > on Windows, where we fight an uphill battle to make Git faster).
>>
>> How expensive gettext() may or may not be isn't relevant to the
>> GETTEXT_POISON compile-time option.
>
> If a user requests NO_GETTEXT, they should have zero (or near zero)
> cost related to gettext. Which is true until now (the inline _()
> version is expanded to pretty much no-op with the exception of NULL
> string)
I'm assuming by "until now" you mean until my RFC patch in
https://public-inbox.org/git/875zxtd59e.fsf@evledraar.gmail.com/
Yeah it's more expensive, but I don't see how it matters. We'd be
nano-optimizing a thing that's never going to become a
bottleneck. I.e. the patch is basically taking the commented-out
codepath in this test program:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int have_flag(void)
{
return 0;
/*
static int flag = -1;
if (flag == -1)
flag = strlen(getenv("GIT_TEST_FOO"));
return flag;
*/
}
int main(void)
{
while (1) {
const char *out = have_flag() ? "foo" : "bar";
puts(out);
}
}
When I test that on my laptop with gcc 8.2.0 I get ~230MB/s of output on
both versions, i.e. where have_flag() can be trivially constant folded,
and where we need to call getenv() for both of:
GIT_TEST_FOO= ./main | pv >/dev/null
GIT_TEST_FOO=1 ./main | pv >/dev/null
We don't have any codepaths where we're calling gettext() to output more
than a screenfull or two of output, so optimizing this doesn't make
sense.
>> The effect of what I'm suggesting here, and which my WIP patch in
>> <875zxtd59e.fsf@evledraar.gmail.com> implements is that we'd do a
>> one-time getenv() for each process that prints a _() message that we
>> aren't doing now, and for each message call a function that would check
>> a boolean "are we in poison mode" static global variable.
>
> Just don't do the getenv() inside _() even if you just do it one time.
> getenv() may invalidate whatever value from the previous call. I would
> not want to find out my code broke because of an getenv() inside some
> innocent _()...
How would any code break? We have various getenv("GIT_TEST_*...")
already that work the same way. Unless you set that in the environment
the function is idempotent, and I don't see how anyone would do that
accidentally.
> And we should still respect NO_GETTEXT, not doing any extra work when
> it's defined.
This is not how any of our NO_* defines work. *Sometimes* defining them
guarantees you do no extra work, but in other cases we've decided that
bending over backwards with #ifdef in various places isn't worth it.
E.g. grep_opt in grep.h is a good example of this. Even if you don't
compile with PCRE you're pointlessly memzero-ing out members of the
struct that'll never be used in your config, because it's easier to
maintain the code that way (types always checked at compile-time).
(And no, despite my involvement in PCRE I didn't introduce that
particular pattern)
For the reasons noted above I think NO_GETTEXT is another such
case. Just like GIT_TEST_SPLIT_INDEX (added in your d6e3c181bc
("read-cache: force split index mode with GIT_TEST_SPLIT_INDEX",
2014-06-13)) etc.
next prev parent reply other threads:[~2018-10-23 16:45 UTC|newest]
Thread overview: 49+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-10-22 15:36 [PATCH] Poison gettext with the Ook language Nguyễn Thái Ngọc Duy
2018-10-22 20:22 ` SZEDER Gábor
2018-10-22 20:22 ` [PATCH 1/8] test-lib.sh: preserve GIT_GETTEXT_POISON from the environment SZEDER Gábor
2018-10-22 20:22 ` [PATCH 2/8] gettext: don't poison if GIT_GETTEXT_POISON is set but empty SZEDER Gábor
2018-10-22 20:38 ` Ævar Arnfjörð Bjarmason
2018-10-22 20:22 ` [PATCH 3/8] lib-rebase: loosen GETTEXT_POISON check in fake editor SZEDER Gábor
2018-10-22 20:22 ` [PATCH 4/8] gettext: #ifdef away GETTEXT POISON-related code from _() and Q_() SZEDER Gábor
2018-10-22 20:22 ` [PATCH 5/8] gettext: put "# GETTEXT POISON #" string literal into a macro SZEDER Gábor
2018-10-22 20:22 ` [PATCH 6/8] gettext: use an enum for the mode of GETTEXT POISONing SZEDER Gábor
2018-10-22 20:22 ` [PATCH 7/8] gettext: introduce GIT_GETTEXT_POISON=scrambled SZEDER Gábor
2018-10-23 14:44 ` Duy Nguyen
2018-10-22 20:22 ` [PATCH 8/8] travis-ci: run GETTEXT POISON build job in scrambled mode, too SZEDER Gábor
2018-10-23 14:37 ` [PATCH] Poison gettext with the Ook language Duy Nguyen
2018-10-27 10:11 ` Jakub Narebski
2018-10-22 20:52 ` Johannes Schindelin
2018-10-22 21:09 ` Ævar Arnfjörð Bjarmason
2018-10-22 21:46 ` Ævar Arnfjörð Bjarmason
2018-10-22 23:04 ` Junio C Hamano
2018-10-23 21:01 ` [PATCH] i18n: make GETTEXT_POISON a runtime option Ævar Arnfjörð Bjarmason
2018-10-24 5:45 ` Junio C Hamano
2018-10-24 7:44 ` Jeff King
2018-10-25 1:00 ` Junio C Hamano
2018-10-25 1:09 ` Jeff King
2018-10-25 1:24 ` Ramsay Jones
2018-10-25 21:23 ` Jeff King
2018-10-26 19:20 ` Ævar Arnfjörð Bjarmason
2018-10-27 6:59 ` Jeff King
2018-10-27 10:42 ` Ævar Arnfjörð Bjarmason
2018-10-24 11:47 ` [PATCH v2] " Ævar Arnfjörð Bjarmason
2018-11-01 19:31 ` [PATCH v3] " Ævar Arnfjörð Bjarmason
2018-11-02 3:11 ` Junio C Hamano
2018-11-02 16:37 ` SZEDER Gábor
2018-11-08 20:26 ` Ævar Arnfjörð Bjarmason
2018-11-08 20:51 ` SZEDER Gábor
2018-11-08 3:24 ` Junio C Hamano
2018-11-08 19:12 ` Eric Sunshine
2018-11-08 21:15 ` [PATCH v4 0/2] " Ævar Arnfjörð Bjarmason
2018-11-08 21:15 ` [PATCH v4 1/2] " Ævar Arnfjörð Bjarmason
2018-11-08 21:15 ` [PATCH v4 2/2] Makefile: ease dynamic-gettext-poison transition Ævar Arnfjörð Bjarmason
2018-10-23 9:30 ` [PATCH] Poison gettext with the Ook language Johannes Schindelin
2018-10-23 10:17 ` Ævar Arnfjörð Bjarmason
2018-10-23 11:07 ` Johannes Schindelin
2018-10-23 15:00 ` Duy Nguyen
2018-10-23 16:45 ` Ævar Arnfjörð Bjarmason [this message]
2018-10-24 14:41 ` Duy Nguyen
2018-10-24 17:54 ` Ævar Arnfjörð Bjarmason
2018-10-25 3:52 ` Junio C Hamano
2018-10-25 6:20 ` Jeff King
2018-10-27 6:55 ` Junio C Hamano
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=871s8gd32p.fsf@evledraar.gmail.com \
--to=avarab@gmail.com \
--cc=Johannes.Schindelin@gmx.de \
--cc=git@vger.kernel.org \
--cc=pclouds@gmail.com \
--cc=szeder.dev@gmail.com \
--cc=vascomalmeida@sapo.pt \
--cc=worldhello.net@gmail.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.
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).