From: Dave Hansen <dave@sr71.net>
To: paulmck@linux.vnet.ibm.com, Peter Zijlstra <peterz@infradead.org>
Cc: Andi Kleen <ak@linux.intel.com>,
dave.hansen@linux.intel.com, akpm@linux-foundation.org,
jack@suse.cz, viro@zeniv.linux.org.uk, eparis@redhat.com,
john@johnmccutchan.com, rlove@rlove.org,
tim.c.chen@linux.intel.com, linux-kernel@vger.kernel.org
Subject: Re: [RFC][PATCH] fs: optimize inotify/fsnotify code for unwatched files
Date: Mon, 22 Jun 2015 11:50:50 -0700 [thread overview]
Message-ID: <5588590A.7080001@sr71.net> (raw)
In-Reply-To: <20150622151121.GK3913@linux.vnet.ibm.com>
On 06/22/2015 08:11 AM, Paul E. McKenney wrote:
> But if Dave is willing to test it, I would be happy to send along
> a fast-readers patch, easy to do.
I'm always willing to test, but the cost of the srcu_read_lock() barrier
shows up even on my 2-year-old "Intel(R) Core(TM) i5-3320M CPU @
2.60GHz" laptop. The numbers I shared in this thread are on a newer CPU
than that, so I'm fairly confident this will show up on just about any
(big core) Intel CPU newer than SandyBridge.
The tests I've been running are:
https://github.com/antonblanchard/will-it-scale
with two new 1-byte read/write tests copied in to "tests/":
https://www.sr71.net/~dave/intel/read1byte.c
https://www.sr71.net/~dave/intel/write1byte.c
The one-byte thing is silly but it does help isolate the kernel's
overhead from what the app is doing.
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next prev parent reply other threads:[~2015-06-22 18:51 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-06-19 21:50 [RFC][PATCH] fs: optimize inotify/fsnotify code for unwatched files Dave Hansen
2015-06-19 23:33 ` Andi Kleen
2015-06-20 0:29 ` Paul E. McKenney
2015-06-20 0:39 ` Dave Hansen
2015-06-20 2:21 ` Paul E. McKenney
2015-06-20 18:02 ` Dave Hansen
2015-06-21 1:30 ` Paul E. McKenney
2015-06-22 13:28 ` Peter Zijlstra
2015-06-22 15:11 ` Paul E. McKenney
2015-06-22 15:20 ` Peter Zijlstra
2015-06-22 16:29 ` Paul E. McKenney
2015-06-22 19:03 ` Peter Zijlstra
2015-06-23 0:31 ` Paul E. McKenney
2015-06-22 18:50 ` Dave Hansen [this message]
2015-06-23 0:26 ` Paul E. McKenney
2015-06-24 16:50 ` Dave Hansen
2015-06-24 17:29 ` Paul E. McKenney
2015-06-22 18:52 ` Peter Zijlstra
2015-06-23 0:29 ` Paul E. McKenney
2015-06-23 15:17 ` Jan Kara
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