From: Matthew Wilcox <matthew@wil.cx>
To: Alexey Dobriyan <adobriyan@gmail.com>
Cc: viro@zeniv.linux.org.uk, linux-fsdevel@vger.kernel.org,
npiggin@kernel.dk
Subject: Re: [PATCH] dcache: faster dentry_cmp()
Date: Tue, 14 Feb 2012 18:41:02 -0700 [thread overview]
Message-ID: <20120215014102.GB5436@parisc-linux.org> (raw)
In-Reply-To: <20120214224526.GA3478@p183.telecom.by>
On Wed, Feb 15, 2012 at 01:45:27AM +0300, Alexey Dobriyan wrote:
> 1) consistently use "unsigned int" for dentry name length,
> 2) reuse subtraction result for return value, exact value doesn't matter
> because function is only used in boolean context,
> 3) use *p++ idiom for even better code.
>
> All of this results in performance speedup of "git diff"
> which is way out of statistical error (0.4% vs 0.15% of 3 sigma):
On what machine, out of interest?
--
Matthew Wilcox Intel Open Source Technology Centre
"Bill, look, we understand that you're interested in selling us this
operating system, but compare it to ours. We can't possibly take such
a retrograde step."
next prev parent reply other threads:[~2012-02-15 1:50 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-02-14 22:45 [PATCH] dcache: faster dentry_cmp() Alexey Dobriyan
2012-02-14 22:58 ` Al Viro
2012-02-15 8:14 ` Alexey Dobriyan
2012-02-15 1:41 ` Matthew Wilcox [this message]
2012-02-15 8:14 ` Alexey Dobriyan
2012-02-15 1:46 ` Andi Kleen
2012-02-15 8:16 ` Alexey Dobriyan
2012-02-15 11:19 ` Alexey Dobriyan
2012-02-15 20:20 ` Andi Kleen
2012-04-20 12:06 ` Nick Piggin
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