<div dir="ltr"><div>never use any of the following software before....just suggest based on reading online:<br></div><div><br></div><div>cyclictest: read this: </div><div><br></div><div><a href="http://www.spinics.net/lists/linux-rt-users/msg04088.html">http://www.spinics.net/lists/linux-rt-users/msg04088.html</a> (as explained within, "timer interrupt latency" is what is being measured by cyclictest.....not sure how it is done).<br>
</div><div><br></div><div>More on cyclictest:</div><div><br></div><div><a href="http://elinux.org/images/0/01/Elc2013_rowand.pdf">http://elinux.org/images/0/01/Elc2013_rowand.pdf</a> <br></div><div><a href="http://people.redhat.com/williams/latency-howto/rt-latency-howto.txt">http://people.redhat.com/williams/latency-howto/rt-latency-howto.txt</a> (last section on different ways of using cyclictest for interrupt latency is covered.)<br>
</div><div><br></div><div>another:</div><div><br></div><div><a href="https://github.com/atlas555/rt-test">https://github.com/atlas555/rt-test</a> (interrupt_tool)</div><div><br></div><div>another is "intrperf" which originate from FreeBSD but there is a Linux version. google for it (<a href="https://repos.dcl.info.waseda.ac.jp/spumone/trac/wiki/Interrupt%20Latency%20of%20Linux%20(intrperf)">https://repos.dcl.info.waseda.ac.jp/spumone/trac/wiki/Interrupt%20Latency%20of%20Linux%20(intrperf)</a> ???).</div>
<div><br></div><div>As highlighted here:</div><div><br></div><div><a href="http://marc.info/?l=linux-smp&m=102733872816465">http://marc.info/?l=linux-smp&m=102733872816465</a><br></div><div><br></div><div>interrupt latencies is really in such smaller order magnitude-wise, or due to low-level CPU feature like I-cache</div>
<div><br></div><div><a href="http://marc.info/?l=linux-arm-kernel&m=107472646713656">http://marc.info/?l=linux-arm-kernel&m=107472646713656</a><br></div><div><br></div><div>that it is not easy nor worth the time tuning.....may be I am wrong.</div>
<div><br></div><div>Check this for another discussion:</div><div><br></div><div><a href="http://marc.info/?t=107403458800005&r=1&w=2">http://marc.info/?t=107403458800005&r=1&w=2</a><br></div><div><br><div class="gmail_extra">
<div class="gmail_quote">On Sun, Mar 16, 2014 at 9:09 PM, loody <span dir="ltr"><<a href="mailto:miloody@gmail.com" target="_blank">miloody@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex">
hi peter:<br>
<br>
<br>
2014-01-17 13:41 GMT+08:00 Peter Teoh <<a href="mailto:htmldeveloper@gmail.com">htmldeveloper@gmail.com</a>>:<br>
> <a href="http://stackoverflow.com/questions/15383259/are-there-any-kernel-tools-available-to-measure-interrupt-latency-with-reasonabl" target="_blank">http://stackoverflow.com/questions/15383259/are-there-any-kernel-tools-available-to-measure-interrupt-latency-with-reasonabl</a><br>
><br>
> checkout cyclictest.<br>
I have checked cyclictest.<br>
from manual page, it seems used to calculate thread latency instead of<br>
interrupt latency<br>
Would you please let me know if there any kind of command for using it<br>
to check interrupt latency ?<br>
thanks fo</blockquote></div>-- <br>Regards,<br>Peter Teoh
</div></div></div>