<div dir="ltr">They are all even numbers :-(<div><br></div><div>This does not play well with our hash if C1 is also even:<div><br></div><div>(((C1 * 23) + P) * 23 + C2) % 8<br></div><div><br></div><div>If C1 is even the C1 * 23 is even. This means ((C1 * 23) + P) * 23 is even. Depending on the value of C2 this means the result is always even or always odd, so with an evenly divisible number of threads you are only ever going to allocate to half of them.</div><div><br></div><div>The good news is this should be easily fixed by using an odd number of IO threads, but we probably should revisit this.</div><div><br></div><div>Stuart</div><div></div></div></div><br><div class="gmail_quote"><div dir="ltr">On Fri, Jul 27, 2018 at 4:34 AM R. Matt Barnett <<a href="mailto:barnett@rice.edu">barnett@rice.edu</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div text="#000000" bgcolor="#FFFFFF">
<p>Backlog setting is 1000.</p>
<p>Is this what you are interested in from netstat? This was for ab
with a -c of 50.<br>
</p>
<p><br>
</p>
<p>[barnett@apigateway_test ~]$ java -jar
undertow-test-0.1.0-jar-with-dependencies.jar &<br>
[1] 7329<br>
[barnett@apigateway_test ~]$ Jul 26, 2018 1:30:22 PM org.xnio.Xnio
<clinit><br>
INFO: XNIO version 3.3.8.Final<br>
Jul 26, 2018 1:30:23 PM org.xnio.nio.NioXnio <clinit><br>
INFO: XNIO NIO Implementation Version 3.3.8.Final<br>
<br>
<br>
Server started on port 8080<br>
1<br>
2<br>
3<br>
4<br>
[barnett@apigateway_test ~]$ netstat -t | grep apigateway_loadge |
grep ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51580 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51614 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51622 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51626 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51612 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51578 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51636 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51616 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51582 ESTABLISHED<br>
tcp6 0 0 apigateway_tes:webcache
apigateway_loadge:51556 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51588 ESTABLISHED<br>
tcp6 0 0 apigateway_tes:webcache
apigateway_loadge:51558 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51586 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51648 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51632 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51652 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51654 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51574 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51640 ESTABLISHED<br>
tcp6 0 0 apigateway_tes:webcache
apigateway_loadge:51564 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51590 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51610 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51594 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51592 ESTABLISHED<br>
tcp6 0 0 apigateway_tes:webcache
apigateway_loadge:51568 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51620 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51598 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51600 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51584 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51630 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51596 ESTABLISHED<br>
tcp6 0 0 apigateway_tes:webcache
apigateway_loadge:51566 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51650 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51656 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51624 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51662 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51642 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51604 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51608 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51634 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51658 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51628 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51660 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51572 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51606 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51602 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51638 ESTABLISHED<br>
tcp6 0 0 apigateway_tes:webcache
apigateway_loadge:51570 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51618 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51646 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51644 ESTABLISHED<br>
tcp6 97 0 apigateway_tes:webcache
apigateway_loadge:51576 ESTABLISHED<br>
</p>
<br>
<div class="m_-2588482696608169146moz-cite-prefix">On 7/25/2018 9:23 PM, Jason Greene
wrote:<br>
</div>
<blockquote type="cite">
<div><span></span></div>
<div>Could you post a netstat output so we can see what port
numbers your host is picking?
<div><br>
</div>
<div>
<div>Also is your backlog setting low by chance? </div>
<div><br>
</div>
<div>On Jul 25, 2018, at 6:24 PM, Stuart Douglas <<a href="mailto:sdouglas@redhat.com" target="_blank">sdouglas@redhat.com</a>>
wrote:<br>
<br>
</div>
<blockquote type="cite">
<div>
<div dir="ltr">The mapping is done by a hash of the remote
IP+port. It sounds like maybe this machine is allocating
ports in a way that does not map well to our hash.
<div><br>
</div>
<div>Because the remote IP is the same it is really only
the port that comes into effect. The algorithm is
in org.xnio.nio.QueuedNioTcpServer#handleReady and in
this case would simplify down to:</div>
<div><br>
</div>
<div>(((C1 * 23) + P) * 23 + C2) % 8</div>
<div><br>
</div>
<div>Where C1 is a hash of the remote IP, and C2 is a
hash of the local IP+port combo. </div>
<div>
<div>
<div><br>
</div>
<div>Stuart</div>
</div>
</div>
</div>
<br>
<div class="gmail_quote">
<div dir="ltr">On Thu, Jul 26, 2018 at 3:52 AM R. Matt
Barnett <<a href="mailto:barnett@rice.edu" target="_blank">barnett@rice.edu</a>>
wrote:<br>
</div>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div text="#000000" bgcolor="#FFFFFF">
<p>I did. I set the concurrency level of ab to 128.
I still see only 4 overlaps:</p>
<blockquote>
<p>$ java -jar
undertow-test-0.1.0-jar-with-dependencies.jar
&<br>
<br>
Server started on port 8080<br>
1<br>
2<br>
3<br>
4<br>
</p>
<p>$ netstat -t | grep apigateway_loadge | grep -c
ESTABLISHED<br>
126</p>
</blockquote>
<p><br>
</p>
<p>What is the algorithm for mapping connections to
IO threads? As a new Undertow user I had assumed
round robin, but it sounds like this is not the
case.</p>
<p><br>
</p>
<p>-- Matt<br>
</p>
<br>
<div class="m_-2588482696608169146m_-3278563139687851367moz-cite-prefix">On
7/25/2018 11:49 AM, Bill O'Neil wrote:<br>
</div>
<blockquote type="cite">
<div dir="ltr">Did you try setting the concurrency
level much higher than 8 like I suggested
earlier? You are probably having multiple
connections assigned to the same IO threads.<input name="virtru-metadata" value="{"email-policy":{"state":"closed","expirationUnit":"days","disableCopyPaste":false,"disablePrint":false,"disableForwarding":false,"expires":false,"isManaged":false},"attachments":{},"compose-window":{"secure":false}}" type="hidden">
<div class="gmail_extra"><br>
<div class="gmail_quote">On Wed, Jul 25, 2018
at 12:26 PM, R. Matt Barnett <span dir="ltr"><<a href="mailto:barnett@rice.edu" target="_blank">barnett@rice.edu</a>></span>
wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Corrected
test to resolve test/set race.<br>
<br>
<br>
<a href="https://gist.github.com/rmbarnett-rice/1179c4ad1d3344bb247c8b8daed3e4fa" rel="noreferrer" target="_blank">https://gist.github.com/rmbarnett-rice/1179c4ad1d3344bb247c8b8daed3e4fa</a><br>
<br>
<br>
I've also discovered this morning that I
*can* see 1-8 printed on Red <br>
Hat when I generate load using ab from
Windows, but only 1-4 when <br>
running ab on Red Hat (both locally and
from a remote server). I'm <br>
wondering if perhaps there is some sort of
connection reuse shenanigans <br>
going on. My assumption of the use of the
-c 8 parameter was "make 8 <br>
sockets" but maybe not. I'll dig in and
report back.<br>
<span class="m_-2588482696608169146m_-3278563139687851367HOEnZb"><font color="#888888"><br>
<br>
-- Matt<br>
</font></span>
<div class="m_-2588482696608169146m_-3278563139687851367HOEnZb">
<div class="m_-2588482696608169146m_-3278563139687851367h5"><br>
<br>
On 7/24/2018 6:56 PM, R. Matt Barnett
wrote:<br>
> Hello,<br>
><br>
> I'm experiencing an Undertow
performance issue I fail to
understand. I<br>
> am able to reproduce the issue
with the code linked bellow. The
problem<br>
> is that on Red Hat (and not
Windows) I'm unable to concurrently
process<br>
> more than 4 overlapping requests
even with 8 configured IO Threads.<br>
> For example, if I run the
following program (1 file, 55 lines):<br>
><br>
> <a href="https://gist.github.com/rmbarnett-rice/668db6b4e9f8f8da7093a3659b6ae2b5" rel="noreferrer" target="_blank">https://gist.github.com/rmbarnett-rice/668db6b4e9f8f8da7093a3659b6ae2b5</a><br>
><br>
> ... on Red Hat and then send
requests to the server using Apache<br>
> Benchmark...<br>
><br>
> > ab -n 1000 -c 8
localhost:8080/<br>
><br>
> I see the following output from
the Undertow process:<br>
><br>
> Server started on port 8080<br>
><br>
> 1<br>
> 2<br>
> 3<br>
> 4<br>
><br>
> I believe this demonstrates that
only 4 requests are ever processed in<br>
> parallel. I would expect 8. In
fact, when I run the same experiment
on<br>
> Windows I see the expected output
of<br>
><br>
> Server started on port 8080<br>
> 1<br>
> 2<br>
> 3<br>
> 4<br>
> 5<br>
> 6<br>
> 7<br>
> 8<br>
><br>
> Any thoughts as to what might
explain this behavior?<br>
><br>
> Best,<br>
><br>
> Matt<br>
><br>
>
_______________________________________________<br>
> undertow-dev mailing list<br>
> <a href="mailto:undertow-dev@lists.jboss.org" target="_blank">undertow-dev@lists.jboss.org</a><br>
> <a href="https://lists.jboss.org/mailman/listinfo/undertow-dev" rel="noreferrer" target="_blank">https://lists.jboss.org/mailman/listinfo/undertow-dev</a><br>
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</blockquote>
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</div>
</blockquote>
<br>
</div>
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<blockquote type="cite">
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