From: Florian Weimer <fw@deneb•enyo.de>
To: git@vger•kernel.org
Subject: Re: [PATCH] Use a hashtable for objects instead of a sorted list
Date: Sun, 12 Feb 2006 12:19:23 +0100 [thread overview]
Message-ID: <87accwlt8k.fsf@mid.deneb.enyo.de> (raw)
In-Reply-To: <7virrli9am.fsf@assigned-by-dhcp.cox.net> (Junio C. Hamano's message of "Sat, 11 Feb 2006 18:46:09 -0800")
* Junio C. Hamano:
> static int hashtable_index(const unsigned char *sha1)
> {
> - unsigned int i = *(unsigned int *)sha1;
> - return (int)(i % obj_allocs);
> + int cnt;
> + unsigned int ix = *sha1++;
> +
> + for (cnt = 1; cnt < sizeof(unsigned int); cnt++) {
> + ix <<= 8;
> + ix |= *sha1++;
> + }
memcpy(&ix, sha1, sizeof(ix));
(GCC should do the rest.)
> + return (int)(ix % obj_allocs);
> }
return (int)(ix & (obj_allocs - 1));
AFAICS, obj_allocs is a power of two.
next prev parent reply other threads:[~2006-02-12 11:19 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-02-11 19:14 [PATCH] Optimization for git-rev-list --objects Alexandre Julliard
2006-02-12 1:57 ` [PATCH] Use a hashtable for objects instead of a sorted list Johannes Schindelin
2006-02-12 2:46 ` Junio C Hamano
2006-02-12 8:52 ` Alexandre Julliard
2006-02-12 12:11 ` Junio C Hamano
2006-02-12 14:31 ` Johannes Schindelin
2006-02-12 11:19 ` Florian Weimer [this message]
2006-02-12 12:08 ` ***DONTUSE*** " Junio C Hamano
2006-02-12 13:46 ` Junio C Hamano
2006-02-12 17:26 ` Johannes Schindelin
2006-02-12 18:34 ` Junio C Hamano
2006-02-12 2:19 ` [PATCH] Optimization for git-rev-list --objects Linus Torvalds
2006-02-12 2:39 ` Junio C Hamano
2006-02-12 4:11 ` [PATCH] binary-tree-based objects Junio C Hamano
2006-02-12 5:06 ` Linus Torvalds
2006-02-12 5:22 ` Linus Torvalds
2006-02-12 5:23 ` Linus Torvalds
2006-02-12 5:48 ` Junio C Hamano
2006-02-12 6:07 ` Junio C Hamano
2006-02-12 6:53 ` Linus Torvalds
2006-02-12 7:05 ` Linus Torvalds
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=87accwlt8k.fsf@mid.deneb.enyo.de \
--to=fw@deneb$(echo .)enyo.de \
--cc=git@vger$(echo .)kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
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