<html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">Amazing. With that option disabled, the runtime falls from 36 seconds to 22 seconds. It also eliminated the significant overhead previously seen when running under the async profiler.<div class=""><br class=""></div><div class="">The system cpu is < 3% and the idle is < 3%. The system % is much closer to the ideal for a test like this. Somewhat unexpected, but any spinning for locks now has a detrimental effect on performance.<br class=""><div class=""><br class=""></div><div class="">In the “real world” test, it didn’t seem to make much difference, but I haven’t fully reviewed that code in light of findings in the micro benchmarks.</div><div class=""><br class=""></div><div class="">The updated profiler shows:</div><div class=""><br class=""></div><div class=""><img apple-inline="yes" id="7E7E876C-100D-4305-B65C-AA2B1CAC21CB" width="640" height="241" src="cid:7DECDBF8-EB47-4343-B75E-90D0D5336175" class=""><br class=""><div><br class=""></div><div>which is interesting because the #1 consumer is still the ForkJoin pool parking while waiting for work - even though the system and idle percentages are so low.</div><div><br class=""></div><div>Can you briefly describe what that runtime option does?</div><div><br class=""></div><div><br class=""><blockquote type="cite" class=""><div class="">On Jan 5, 2023, at 1:05 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="">
On 05/01/2023 00:54, robert engels wrote:<br class="">
<blockquote type="cite" cite="mid:BDF8EDE2-346B-47D1-A49C-284EDDEA669C@ix.netcom.com" class="">
<br class="">
<div class=""><br class="">
<blockquote type="cite" class="">
<div class="">On Jan 4, 2023, at 3:32 AM, Alan Bateman <<a href="mailto:Alan.Bateman@oracle.com" class="moz-txt-link-freetext" moz-do-not-send="true">Alan.Bateman@oracle.com</a>>
wrote:</div>
<br class="Apple-interchange-newline">
<div class=""><span style="caret-color: rgb(0, 0, 0);
font-family: Helvetica; font-size: 16px; font-style:
normal; font-variant-caps: normal; font-weight: 400;
letter-spacing: normal; text-align: start; text-indent:
0px; text-transform: none; white-space: normal;
word-spacing: 0px; -webkit-text-stroke-width: 0px;
text-decoration: none; float: none; display: inline
!important;" class="">-XX:+UnlockExperimentalVMOptions
-XX:+DoJVMTIVirtualThreadTransitions<span class="Apple-converted-space"> </span></span></div>
</blockquote>
</div>
<br class="">
<div class="">As an fyi, the above did not affect the async
profiler trace that I could tell. I get similar profilers with
both the Intellij profiler and the async profiler.</div>
</blockquote>
<br class="">
Oops, a typo in my mail, it should be <span style="caret-color:
rgb(0, 0, 0); font-family: Helvetica; font-size: 16px; font-style:
normal; font-variant-caps: normal; font-weight: 400;
letter-spacing: normal; text-align: start; text-indent: 0px;
text-transform: none; white-space: normal; word-spacing: 0px;
-webkit-text-stroke-width: 0px; text-decoration: none; float:
none; display: inline !important;" class="">-XX:-DoJVMTIVirtualThreadTransitions<span class="Apple-converted-space"> to disable (not '+' to enable).<br class="">
<br class="">
-Alan<br class="">
</span></span>
</div>
</div></blockquote></div><br class=""></div></div></body></html>