From: Vince Weaver <vincent.weaver@maine.edu>
To: Benjamin King <benjaminking@web.de>
Cc: Milian Wolff <milian.wolff@kdab.com>, linux-perf-users@vger.kernel.org
Subject: Re: How to sample memory usage cheaply?
Date: Sat, 1 Apr 2017 09:54:02 -0400 (EDT) [thread overview]
Message-ID: <alpine.DEB.2.20.1704010952260.19001@macbook-air> (raw)
In-Reply-To: <20170401074112.GA8989@localhost>
On Sat, 1 Apr 2017, Benjamin King wrote:
> Also, the 'perf stat' output that I sent does not make much sense to me right
> now. For example, when I add MAP_POPULATE to the flags for mmap, I only see
> ~40 minor page faults, which I do not understand at all.
have you tried accessing your file in random order? I think the kernel is
likely doing some sort of readahead/prefetching. I think you can change
that behavior with the madvise() syscall
Vince
next prev parent reply other threads:[~2017-04-01 13:54 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-03-30 20:04 How to sample memory usage cheaply? Benjamin King
2017-03-31 12:06 ` Milian Wolff
2017-04-01 7:41 ` Benjamin King
2017-04-01 13:54 ` Vince Weaver [this message]
2017-04-01 16:27 ` Benjamin King
2017-04-03 19:09 ` Benjamin King
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