From: Al Viro <viro@zeniv.linux.org.uk>
To: Matthew Wilcox <willy@infradead.org>
Cc: "zhengbin (A)" <zhengbin13@huawei.com>,
Hugh Dickins <hughd@google.com>,
linux-mm@kvack.org, linux-kernel@vger.kernel.org,
houtao1@huawei.com, yi.zhang@huawei.com,
"J. R. Okajima" <hooanon05g@gmail.com>,
Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH] tmpfs: use ida to get inode number
Date: Sat, 23 Nov 2019 04:54:44 +0000 [thread overview]
Message-ID: <20191123045444.GI26530@ZenIV.linux.org.uk> (raw)
In-Reply-To: <20191123023325.GY20752@bombadil.infradead.org>
On Fri, Nov 22, 2019 at 06:33:25PM -0800, Matthew Wilcox wrote:
> On Sat, Nov 23, 2019 at 10:16:39AM +0800, zhengbin (A) wrote:
> > By the way, percpu IDA is for reducing performance impact? This patch has 2.16%
> > performance degradation(Use perf to get the cost of ida_alloc_range)
>
> 2.16% degradation in your tests ... I bet Eric didn't make it so complex
> for only 2% performance impact. Unfortunately, he didn't give any
> numbers in his patch submission, but it's going to be a bigger problem
> on multi-socket machines than on a laptop.
It could also be that socket(2) is called (on real loads) just a bit
more often than open(2) in a benchmark that tests file creation...
next prev parent reply other threads:[~2019-11-23 4:54 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-11-20 14:23 zhengbin
2019-11-20 15:45 ` Matthew Wilcox
2019-11-21 2:36 ` zhengbin (A)
2019-11-21 4:52 ` Hugh Dickins
2019-11-21 6:45 ` zhengbin (A)
2019-11-21 19:53 ` Hugh Dickins
2019-11-22 1:23 ` zhengbin (A)
2019-11-22 22:13 ` Matthew Wilcox
2019-11-23 2:16 ` zhengbin (A)
2019-11-23 2:33 ` Matthew Wilcox
2019-11-23 4:54 ` Al Viro [this message]
2019-12-01 8:44 ` zhengbin (A)
2019-11-21 11:40 ` J. R. Okajima
2019-11-21 20:07 ` Hugh Dickins
2019-11-21 4:31 ` Al Viro
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=20191123045444.GI26530@ZenIV.linux.org.uk \
--to=viro@zeniv.linux.org.uk \
--cc=eric.dumazet@gmail.com \
--cc=hooanon05g@gmail.com \
--cc=houtao1@huawei.com \
--cc=hughd@google.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=willy@infradead.org \
--cc=yi.zhang@huawei.com \
--cc=zhengbin13@huawei.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