From: Linus Torvalds <torvalds@osdl.org>
To: Chris Wedgwood <cw@f00f.org>
Cc: Git Mailing List <git@vger.kernel.org>
Subject: Re: Careful object writing..
Date: Tue, 3 May 2005 12:47:36 -0700 (PDT) [thread overview]
Message-ID: <Pine.LNX.4.58.0505031242330.26698@ppc970.osdl.org> (raw)
In-Reply-To: <20050503192753.GA6435@taniwha.stupidest.org>
On Tue, 3 May 2005, Chris Wedgwood wrote:
>
> how is this better than a single rename? i take it there is something
> fundamental from clue.101 i slept though here?
A rename will overwrite any old object, which means that you cannot do any
collision checks. In contrast, a "link()" will return EEXIST if somebody
else raced with you and created a new object, and you can do collision
checks instead of overwriting another persons object.
> also, if you are *really* paranoid you want to fsync *before* you do
> the link/unklink or rename --- which is what MTAs do[1]
Me, I refuse to slow down my habits for old filesystems. You can either
fsck, or use a logging filesystem.
I don't see anybody not using logging filesystems these days, so..
> also, shouldn't HEAD (and similar)[2] be updated with a temporary and
> a rename too?
Maybe. Much less important, though.
> > NOTE NOTE NOTE! I have _not_ updated all the helper stuff that also
> > write objects.
>
> i thought this was all common code? if it's not maybe now is the time
> to change that?
It is all common code, except:
- things like "fetch from another host" will use rsync/wget/xxx to
actually get the files. To those programs, we're not talking about git
objects, we're just talking "regular files"
- rpull.c has a special different routine to write its objects. I don't
use it, so..
Anyway, it should be reasonably easily fixable.
Linus
next prev parent reply other threads:[~2005-05-03 19:39 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2005-05-03 19:15 Careful object writing Linus Torvalds
2005-05-03 19:27 ` Chris Wedgwood
2005-05-03 19:47 ` Linus Torvalds [this message]
2005-05-03 19:47 ` Chris Wedgwood
2005-05-03 19:56 ` Linus Torvalds
2005-05-03 20:02 ` Daniel Barkalow
2005-05-03 20:00 ` Jan Harkes
2005-05-03 20:11 ` Linus Torvalds
2005-05-03 20:59 ` Jan Harkes
2005-05-03 22:13 ` Linus Torvalds
2005-05-03 22:37 ` Linus Torvalds
2005-05-03 22:40 ` H. Peter Anvin
2005-05-03 23:04 ` Alex Riesen
2005-05-03 23:22 ` Linus Torvalds
2005-05-03 23:25 ` Alex Riesen
2005-05-03 23:22 ` Junio C Hamano
2005-05-04 4:07 ` [PATCH] Careful object pulling Daniel Barkalow
2005-05-04 9:35 ` Morten Welinder
2005-05-04 16:16 ` Daniel Barkalow
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=Pine.LNX.4.58.0505031242330.26698@ppc970.osdl.org \
--to=torvalds@osdl.org \
--cc=cw@f00f.org \
--cc=git@vger.kernel.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).