From: Johannes Sixt <j6t@kdbg.org>
To: Stefan Beller <sbeller@google.com>, Junio C Hamano <gitster@pobox.com>
Cc: "git@vger.kernel.org" <git@vger.kernel.org>,
Ramsay Jones <ramsay@ramsayjones.plus.com>,
Jacob Keller <jacob.keller@gmail.com>, Jeff King <peff@peff.net>,
Jonathan Nieder <jrnieder@gmail.com>,
Johannes Schindelin <johannes.schindelin@gmail.com>,
Jens Lehmann <Jens.Lehmann@web.de>,
Eric Sunshine <ericsunshine@gmail.com>
Subject: Re: [PATCHv3 02/11] run-command: report failure for degraded output just once
Date: Wed, 4 Nov 2015 21:36:13 +0100 [thread overview]
Message-ID: <563A6C3D.2050805@kdbg.org> (raw)
In-Reply-To: <CAGZ79kaiRKHd2RS9eNeZt_VZqqBF0HS0D=x1HbOTPXYOphu8pg@mail.gmail.com>
Am 04.11.2015 um 21:14 schrieb Stefan Beller:
> On Wed, Nov 4, 2015 at 10:14 AM, Junio C Hamano <gitster@pobox.com> wrote:
>> Imagine that we are running two things A and B at the same time. We
>> ask poll(2) and it says both A and B have some data ready to be
>> read, and we try to read from A. strbuf_read_once() would try to
>> read up to 8K, relying on the fact that you earlier set the IO to be
>> nonblock. It will get stuck reading from A without allowing output
>> from B to drain. B's write may get stuck because we are not reading
>> from it, and would cause B to stop making progress.
>>
>> What if the other sides of the connection from A and B are talking
>> with each other,
>
> I am not sure if we want to allow this ever. How would that work with
> jobs==1? How do we guarantee to have A and B running at the same time?
I think that a scenario where A and B are communicating is rather
far-fetched. We are talking about parallelizing independent tasks. I
would not worry.
-- Hannes
next prev parent reply other threads:[~2015-11-04 20:36 UTC|newest]
Thread overview: 34+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-11-04 0:37 [PATCHv3 00/11] Expose the submodule parallelism to the user Stefan Beller
2015-11-04 0:37 ` [PATCHv3 01/11] run_processes_parallel: delimit intermixed task output Stefan Beller
2015-11-04 0:37 ` [PATCHv3 02/11] run-command: report failure for degraded output just once Stefan Beller
2015-11-04 18:14 ` Junio C Hamano
2015-11-04 20:14 ` Stefan Beller
2015-11-04 20:36 ` Johannes Sixt [this message]
2015-11-04 21:01 ` Junio C Hamano
2015-11-04 22:56 ` Jeff King
2015-11-05 2:05 ` Junio C Hamano
2015-11-05 6:51 ` Jeff King
2015-11-05 7:32 ` Junio C Hamano
2015-11-05 17:37 ` Stefan Beller
2015-11-04 20:42 ` Junio C Hamano
2015-11-04 21:04 ` Stefan Beller
2015-11-04 21:19 ` Junio C Hamano
2015-11-04 21:41 ` Stefan Beller
2015-11-04 0:37 ` [PATCHv3 03/11] run-command: omit setting file descriptors to non blocking in Windows Stefan Beller
2015-11-04 0:37 ` [PATCHv3 04/11] submodule-config: keep update strategy around Stefan Beller
2015-11-04 0:37 ` [PATCHv3 05/11] submodule-config: drop check against NULL Stefan Beller
2015-11-04 0:37 ` [PATCHv3 06/11] submodule-config: remove name_and_item_from_var Stefan Beller
2015-11-04 0:37 ` [PATCHv3 07/11] submodule-config: introduce parse_generic_submodule_config Stefan Beller
2015-11-04 0:37 ` [PATCHv3 08/11] fetching submodules: respect `submodule.jobs` config option Stefan Beller
2015-11-10 22:21 ` Jens Lehmann
2015-11-10 22:29 ` Stefan Beller
2015-11-11 19:55 ` Jens Lehmann
2015-11-11 23:34 ` Stefan Beller
2015-11-13 20:47 ` Jens Lehmann
2015-11-13 21:29 ` Stefan Beller
2015-11-04 0:37 ` [PATCHv3 09/11] git submodule update: have a dedicated helper for cloning Stefan Beller
2015-11-04 0:37 ` [PATCHv3 10/11] submodule update: expose parallelism to the user Stefan Beller
2015-11-04 0:37 ` [PATCHv3 11/11] clone: allow an explicit argument for parallel submodule clones Stefan Beller
2015-11-04 17:54 ` [PATCHv3 00/11] Expose the submodule parallelism to the user Junio C Hamano
2015-11-04 18:08 ` Stefan Beller
2015-11-04 18:17 ` 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
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=563A6C3D.2050805@kdbg.org \
--to=j6t@kdbg.org \
--cc=Jens.Lehmann@web.de \
--cc=ericsunshine@gmail.com \
--cc=git@vger.kernel.org \
--cc=gitster@pobox.com \
--cc=jacob.keller@gmail.com \
--cc=johannes.schindelin@gmail.com \
--cc=jrnieder@gmail.com \
--cc=peff@peff.net \
--cc=ramsay@ramsayjones.plus.com \
--cc=sbeller@google.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 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 NNTP newsgroup(s).