From: stillcompiling@gmail.com (Joshua Clayton)
To: linux-arm-kernel@lists.infradead.org
Subject: [OT] Profiling on ARM Linux systems: how?
Date: Wed, 29 Apr 2015 08:29:45 -0700 [thread overview]
Message-ID: <1516029.oc3LenLXRM@jclayton-pc> (raw)
In-Reply-To: <mhqrbj$vlu$1@ger.gmane.org>
On Wednesday, April 29, 2015 02:54:43 PM Grant Edwards wrote:
> This might be a little off-topic. If so I apologize.
Probably.
>
> I have a problem with excessive CPU usage on an embedded ARM926
> system. There are three main apps, all of which have multiple
> threads. The total CPU usage is too high. I'm trying to figure out
> where the CPU time is "going" so we know were to concentrate
> optimization efforts.
>
> The "top" utility is useless because it samples at a fixed interval.
> Almost all of the threads are driven by timers on fixed cycles (or
> data from threads that are). The 'top' sampling method appears to
> cause aliasing which renders the numbers shown by top meaningless.
>
...
>
> Any advice?
At my company we have found perf top more useful than top
for finding performance problems that might include kernel interaction.
perf has a number of other goodies as well that are worth a look.
Beyond that, idk.
--
~Joshua Clayton
prev parent reply other threads:[~2015-04-29 15:29 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-04-29 14:54 [OT] Profiling on ARM Linux systems: how? Grant Edwards
2015-04-29 15:29 ` Joshua Clayton [this message]
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