<html><head><meta http-equiv="Content-Type" content="text/html; charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">I noticed the errors too, but I have tested with two different client impls and two different server impls, and both report similar error rates (about .25%). I believe it is the OSX networking layer closing connections due to lack of buffer space or detecting what it thinks is a DoS attack.<div class=""><br class=""></div><div class="">Anyway, with a different client (no http pipelining) I get similar results:</div><div class=""><br class=""></div><div class="">With default parallelism:</div><div class=""><br class=""></div><div class=""><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 12px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">robertengels@macmini go-wrk % wrk -H 'Host: imac' -H 'Accept: text/plain,text/html;q=0.9,application/xhtml+xml;q=0.9,application/xml;q=0.8,*/*;q=0.7' -H 'Connection: keep-alive' --latency -d 20 -c 1000 --timeout 8 -t 8 <a href="http://imac:8080/plaintext" class="">http://imac:8080/plaintext</a></span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 12px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">Running 20s test @ <a href="http://imac:8080/plaintext" class="">http://imac:8080/plaintext</a></span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 12px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> 8 threads and 1000 connections</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 12px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> Thread Stats Avg Stdev Max +/- Stdev</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 12px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> Latency 60.53ms 137.57ms 2.41s 88.69%</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 12px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> Req/Sec 14.71k 2.13k 22.55k 77.25%</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 12px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> Latency Distribution</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 12px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> 50% 4.98ms</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 12px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> 75% 34.80ms</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 12px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> 90% 229.44ms</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 12px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> 99% 658.57ms</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 12px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> 2342553 requests in 20.02s, 317.23MB read</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 12px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> Socket errors: connect 0, read 1926, write 4, timeout 0</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 12px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">Requests/sec: 116990.94</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 12px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">Transfer/sec: 15.84MB</span></div><div class=""><span style="font-variant-ligatures: no-common-ligatures" class=""><br class=""></span></div><div>and with parallelism=3:</div><div><br class=""></div><div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 12px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">robertengels@macmini go-wrk % wrk -H 'Host: imac' -H 'Accept: text/plain,text/html;q=0.9,application/xhtml+xml;q=0.9,application/xml;q=0.8,*/*;q=0.7' -H 'Connection: keep-alive' --latency -d 20 -c 1000 --timeout 8 -t 8 <a href="http://imac:8080/plaintext" class="">http://imac:8080/plaintext</a></span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 12px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">Running 20s test @ <a href="http://imac:8080/plaintext" class="">http://imac:8080/plaintext</a></span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 12px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> 8 threads and 1000 connections</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 12px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> Thread Stats Avg Stdev Max +/- Stdev</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 12px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> Latency 39.91ms 90.53ms 822.66ms 89.29%</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 12px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> Req/Sec 14.99k 2.84k 23.83k 75.06%</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 12px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> Latency Distribution</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 12px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> 50% 6.62ms</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 12px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> 75% 9.54ms</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 12px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> 90% 148.83ms</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 12px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> 99% 392.24ms</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 12px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> 2386247 requests in 20.02s, 323.15MB read</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 12px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> Socket errors: connect 0, read 2833, write 5, timeout 0</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 12px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">Requests/sec: 119201.21</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 12px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">Transfer/sec: 16.14MB</span></div></div><div><br class=""></div><div>and similarly, the default parallelism shows much higher cpu usage - 8% idle vs 25% idle for the latter.</div><div><br class=""></div><div>Using VT pollers (pollerMode=2) and default parallelism:</div><div><br class=""></div><div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 13px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">robertengels@macmini go-wrk % wrk -H 'Host: imac' -H 'Accept: text/plain,text/html;q=0.9,application/xhtml+xml;q=0.9,application/xml;q=0.8,*/*;q=0.7' -H 'Connection: keep-alive' --latency -d 20 -c 1000 --timeout 8 -t 8 <a href="http://imac:8080/plaintext" class="">http://imac:8080/plaintext</a></span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 13px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">Running 20s test @ <a href="http://imac:8080/plaintext" class="">http://imac:8080/plaintext</a></span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 13px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> 8 threads and 1000 connections</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 13px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> Thread Stats Avg Stdev Max +/- Stdev</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 13px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> Latency 66.76ms 137.25ms 1.70s 87.06%</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 13px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> Req/Sec 14.38k 2.36k 21.94k 75.88%</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 13px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> Latency Distribution</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 13px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> 50% 4.74ms</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 13px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> 75% 51.68ms</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 13px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> 90% 263.08ms</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 13px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> 99% 664.99ms</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 13px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> 2289858 requests in 20.02s, 310.10MB read</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 13px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> Socket errors: connect 0, read 2135, write 7, timeout 0</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 13px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">Requests/sec: 114360.91</span></div><div style="margin: 0px; font-stretch: normal; line-height: normal; font-family: Menlo; color: rgb(0, 0, 0); font-size: 13px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">Transfer/sec: 15.49MB</span></div></div><div><br class=""></div><div>and the same 8% idle.</div><div><br class=""></div><div>So I am pretty sure my hypothesis is correct. I may try and build a Loom / use a library to lower priority of the carrier threads. I suspect I will see similar performance to the reduced parallelism case.</div><div><br class=""><blockquote type="cite" class=""><div class="">On Aug 13, 2024, at 2:25 AM, Alan Bateman <<a href="mailto:alan.bateman@oracle.com" class="">alan.bateman@oracle.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class="">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" class="">
<div class="">
<br class="">
<br class="">
<div class="moz-cite-prefix">On 12/08/2024 20:29, Robert Engels
wrote:<br class="">
</div>
<blockquote type="cite" cite="mid:ECF1EE89-3253-447C-BC75-84DF26C1FD5E@icloud.com" class="">
<pre class="moz-quote-pre" wrap="">Sorry, I should have included that. I am using (build 24-loom+3-33) - which is still using Pollers.
</pre>
</blockquote>
That's based on jdk-24+8 so up to date.<br class="">
<br class="">
There are two "poller modes". On macOS it uses the "system thread"
poller mode by default but you can experiment with
-Djdk.pollerMode=2 to have the poller threads be virtual threads,
same as the default on Linux. To do this will also mean setting
-Djdk.readPollers=4 or some power of 2 value. Our testing on macOS
some time ago didn't converge on the best default.<br class="">
<br class="">
There seems to be a lot of errors (broken pipe, connection reset,
and other timeouts) in your results. Do you have some TCP/networking
tuning to remove these from the runs as I assume timeouts will skew
some of the results.<br class="">
<br class="">
-Alan<br class="">
</div>
</div></blockquote></div><br class=""></div></body></html>