From: Jeff King <peff@peff.net>
To: Patrick Steinhardt <ps@pks.im>
Cc: git@vger.kernel.org, Junio C Hamano <gitster@pobox.com>,
Johannes Schindelin <Johannes.Schindelin@gmx.de>
Subject: Re: [PATCH 3/9] t4141: fix inefficient use of dd(1)
Date: Fri, 3 Jul 2026 03:00:30 -0400 [thread overview]
Message-ID: <20260703070030.GA2082500@coredump.intra.peff.net> (raw)
In-Reply-To: <akdLqNHW3pGThQat@pks.im>
On Fri, Jul 03, 2026 at 07:42:00AM +0200, Patrick Steinhardt wrote:
> > It feels like test_copy_bytes should be able to do much better in
> > general. The obvious thing to reach for is "head -c", but the function
> > was originally added because that wasn't portable. The "-c" option is
> > not in POSIX, though the original comment claims IRIX was the problem,
> > so I wonder if "head -c" is de facto portable these days.
>
> An alternative could be to implement a simple helper as part of our
> test-tool. But I doubt it's really worth it: almost all callers only
> want to copy a small number of bytes. The only exception seems to be
> t0021, where we copy up to 65kB. But that whole test suite still only
> takes ~3 seconds, so optimizing that feels like wasted time to me.
Yeah, you're probably right that it's not worth worrying too much about.
-Peff
next prev parent reply other threads:[~2026-07-03 7:00 UTC|newest]
Thread overview: 45+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-07-02 12:00 [PATCH 0/9] t: fixes and improvements for GIT_TEST_LONG Patrick Steinhardt
2026-07-02 12:00 ` [PATCH 1/9] README: add GitLab CI badge to make it more discoverable Patrick Steinhardt
2026-07-02 12:00 ` [PATCH 2/9] t0021: skip EXPENSIVE test that is broken without SIZE_T_IS_32BIT Patrick Steinhardt
2026-07-02 12:00 ` [PATCH 3/9] t4141: fix inefficient use of dd(1) Patrick Steinhardt
2026-07-02 17:49 ` SZEDER Gábor
2026-07-03 5:42 ` Patrick Steinhardt
2026-07-02 21:16 ` Jeff King
2026-07-03 5:42 ` Patrick Steinhardt
2026-07-03 7:00 ` Jeff King [this message]
2026-07-02 12:00 ` [PATCH 4/9] t5608: reduce maximum disk usage Patrick Steinhardt
2026-07-02 12:00 ` [PATCH 5/9] t7508: skip EXPENSIVE test that is broken without SIZE_T_IS_32BIT Patrick Steinhardt
2026-07-02 21:22 ` Jeff King
2026-07-02 22:18 ` Jeff King
2026-07-02 12:00 ` [PATCH 6/9] t7900: clean up large EXPENSIVE repository Patrick Steinhardt
2026-07-02 21:30 ` Jeff King
2026-07-03 5:42 ` Patrick Steinhardt
2026-07-03 7:00 ` Jeff King
2026-07-02 12:01 ` [PATCH 7/9] t: use `test_bool_env` to parse GIT_TEST_LONG Patrick Steinhardt
2026-07-02 12:01 ` [PATCH 8/9] gitlab-ci: disable RAM disk on macOS jobs Patrick Steinhardt
2026-07-02 12:01 ` [PATCH 9/9] gitlab-ci: enable "GIT_TEST_LONG" Patrick Steinhardt
2026-07-03 9:24 ` [PATCH v2 0/9] t: fixes and improvements for GIT_TEST_LONG Patrick Steinhardt
2026-07-03 9:24 ` [PATCH v2 1/9] README: add GitLab CI badge to make it more discoverable Patrick Steinhardt
2026-07-03 9:24 ` [PATCH v2 2/9] t0021: skip EXPENSIVE test that is broken without SIZE_T_IS_32BIT Patrick Steinhardt
2026-07-03 17:36 ` Junio C Hamano
2026-07-06 6:23 ` Patrick Steinhardt
2026-07-03 9:24 ` [PATCH v2 3/9] t4141: fix inefficient use of dd(1) Patrick Steinhardt
2026-07-03 9:24 ` [PATCH v2 4/9] t5608: reduce maximum disk usage Patrick Steinhardt
2026-07-03 9:24 ` [PATCH v2 5/9] t7508: skip EXPENSIVE test that is broken without SIZE_T_IS_32BIT Patrick Steinhardt
2026-07-03 17:38 ` Junio C Hamano
2026-07-03 9:24 ` [PATCH v2 6/9] t7900: clean up large EXPENSIVE repository Patrick Steinhardt
2026-07-03 9:24 ` [PATCH v2 7/9] t: use `test_bool_env` to parse GIT_TEST_LONG Patrick Steinhardt
2026-07-03 9:24 ` [PATCH v2 8/9] gitlab-ci: disable RAM disk on macOS jobs Patrick Steinhardt
2026-07-03 9:24 ` [PATCH v2 9/9] gitlab-ci: enable "GIT_TEST_LONG" Patrick Steinhardt
2026-07-06 6:23 ` [PATCH v3 0/9] t: fixes and improvements for GIT_TEST_LONG Patrick Steinhardt
2026-07-06 6:23 ` [PATCH v3 1/9] README: add GitLab CI badge to make it more discoverable Patrick Steinhardt
2026-07-06 6:23 ` [PATCH v3 2/9] t0021: skip EXPENSIVE test that is broken without SIZE_T_IS_64BIT Patrick Steinhardt
2026-07-06 6:23 ` [PATCH v3 3/9] t4141: fix inefficient use of dd(1) Patrick Steinhardt
2026-07-06 6:23 ` [PATCH v3 4/9] t5608: reduce maximum disk usage Patrick Steinhardt
2026-07-06 6:24 ` [PATCH v3 5/9] t7508: skip EXPENSIVE test that is broken without SIZE_T_IS_64BIT Patrick Steinhardt
2026-07-06 6:24 ` [PATCH v3 6/9] t7900: clean up large EXPENSIVE repository Patrick Steinhardt
2026-07-06 6:24 ` [PATCH v3 7/9] t: use `test_bool_env` to parse GIT_TEST_LONG Patrick Steinhardt
2026-07-06 6:24 ` [PATCH v3 8/9] gitlab-ci: disable RAM disk on macOS jobs Patrick Steinhardt
2026-07-06 6:24 ` [PATCH v3 9/9] gitlab-ci: enable "GIT_TEST_LONG" Patrick Steinhardt
2026-07-06 20:29 ` [PATCH v3 0/9] t: fixes and improvements for GIT_TEST_LONG Junio C Hamano
2026-07-07 4:30 ` Jeff King
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