From: Andrew Morton <akpm@osdl.org>
To: wcheng@redhat.com
Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH] prune_icache_sb
Date: Sun, 3 Dec 2006 22:28:16 -0800 [thread overview]
Message-ID: <20061203222816.aaef93a3.akpm@osdl.org> (raw)
In-Reply-To: <4573B8DE.20205@redhat.com>
On Mon, 04 Dec 2006 00:57:50 -0500
Wendy Cheng <wcheng@redhat.com> wrote:
> >
> >
> >>>Did you look at improving that lock-lookup algorithm, btw? Core kernel has
> >>>no problem maintaining millions of cached VFS objects - is there any reason
> >>>why your lock lookup cannot be similarly efficient?
> >>>
> >>>
> >>>
> Yes, just found the new DLM uses "jhash" call (include/linux/jhash.h).
> I'm on an older version of DLM that uses FNV hash algorithm
> (http://www.isthe.com/chongo/tech/comp/fnv/). Will do some performance
> test runs to compare these two methods.
I'd be surprised if the choice of hash algorithm itself makes much difference.
But we can't say much about it unless we can see the code (ie: your code).
Is it a simple old hash-to-find-the-bucket-then-walk-a-list implementation?
If so, what does the bucket count distribution look like? What is the average
walk length? Does it use a single lock, or hashed locking, or a lock-per-bucket?
etc.
next prev parent reply other threads:[~2006-12-04 6:28 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-11-22 21:35 Wendy Cheng
2006-11-22 23:36 ` Andrew Morton
2006-11-27 23:52 ` Wendy Cheng
2006-11-28 0:52 ` Andrew Morton
2006-11-28 21:41 ` Wendy Cheng
2006-11-29 0:21 ` Andrew Morton
2006-11-29 6:02 ` Wendy Cheng
2006-11-30 16:05 ` Wendy Cheng
2006-11-30 19:31 ` Nate Diller
2006-12-01 21:23 ` Andrew Morton
2006-12-03 17:49 ` Wendy Cheng
2006-12-03 20:47 ` Andrew Morton
2006-12-04 5:57 ` Wendy Cheng
2006-12-04 6:28 ` Andrew Morton [this message]
2006-12-04 16:41 ` [PATCH] SLAB : use a multiply instead of a divide in obj_to_index() Eric Dumazet
2006-12-04 16:55 ` Christoph Lameter
2006-12-04 18:18 ` Eric Dumazet
2006-12-04 19:49 ` Andrew Morton
2006-12-04 19:55 ` Christoph Lameter
2006-12-04 21:34 ` Eric Dumazet
2006-12-04 21:56 ` David Miller
2006-12-04 22:45 ` Eric Dumazet
2006-12-05 14:42 ` Pavel Machek
2006-12-04 16:51 ` [PATCH] prune_icache_sb Russell Cattelan
2006-12-04 20:46 ` Wendy Cheng
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=20061203222816.aaef93a3.akpm@osdl.org \
--to=akpm@osdl.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=wcheng@redhat.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
Powered by JetHome