From: Jeff King <peff@peff.net>
To: Duy Nguyen <pclouds@gmail.com>
Cc: Junio C Hamano <gitster@pobox.com>,
Johannes Schindelin via GitGitGadget <gitgitgadget@gmail.com>,
Git Mailing List <git@vger.kernel.org>,
Johannes Schindelin <johannes.schindelin@gmx.de>
Subject: Re: [PATCH 4/3] untracked-cache: use FLEX_ALLOC to create internal structs
Date: Fri, 19 Apr 2019 15:43:29 -0400 [thread overview]
Message-ID: <20190419194329.GA28277@sigill.intra.peff.net> (raw)
In-Reply-To: <CACsJy8BHwM5dUqa-FOjr3smxJT6kW4z7vLUJvsHuhjxwUjvkBw@mail.gmail.com>
On Fri, Apr 19, 2019 at 04:18:25PM +0700, Duy Nguyen wrote:
> > I also wondered if we could just accept the cost of calloc() here and
> > use FLEX_ALLOC to simplify things. That resulted in the patch below, but
> > I didn't include it with the initial 3, because I think it's too
> > subtle/gross for my tastes.
>
> It's probably ok. If I remember correctly, reading UNTR extension (on
> a huge repo) took the longest time after Ben added support for reading
> the index with multiple threads. So performance is a concern, but I
> don't think calloc() would be the problem. malloc() itself without the
> memory pool could probably slow down more when we have lots and lots
> of directories.
I think if we do the FLEX_ALLOC_COPY() thing I mentioned that it would
probably _not_ use calloc() there, since we'd know we were copying in
the content from elsewhere. So that concern would go away either way. :)
(But I'm still skeptical that FLEX_ALLOC_COPY() is worth it unless we
can find at least one other caller).
-Peff
prev parent reply other threads:[~2019-04-19 19:43 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-04-10 12:56 [PATCH 0/1] Fix an off-by-one bug in the untracked cache code Johannes Schindelin via GitGitGadget
2019-04-10 12:56 ` [PATCH 1/1] untracked cache: fix off-by-one Johannes Schindelin via GitGitGadget
2019-04-10 16:20 ` Jeff King
2019-04-12 1:48 ` Junio C Hamano
2019-04-18 21:14 ` [PATCH 0/3] untracked cache parsing fixups Jeff King
2019-04-18 21:17 ` [PATCH 1/3] untracked-cache: be defensive about missing NULs in index Jeff King
2019-04-19 5:29 ` Junio C Hamano
2019-04-18 21:17 ` [PATCH 2/3] untracked-cache: simplify parsing by dropping "next" Jeff King
2019-04-19 5:33 ` Junio C Hamano
2019-04-18 21:18 ` [PATCH 3/3] untracked-cache: simplify parsing by dropping "len" Jeff King
2019-04-18 21:24 ` [PATCH 4/3] untracked-cache: use FLEX_ALLOC to create internal structs Jeff King
2019-04-19 9:18 ` Duy Nguyen
2019-04-19 19:43 ` Jeff King [this message]
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=20190419194329.GA28277@sigill.intra.peff.net \
--to=peff@peff.net \
--cc=git@vger.kernel.org \
--cc=gitgitgadget@gmail.com \
--cc=gitster@pobox.com \
--cc=johannes.schindelin@gmx.de \
--cc=pclouds@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).