<html><head><style>body{font-family:Helvetica,Arial;font-size:13px}</style></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;"><div id="bloop_customfont" style="font-family:Helvetica,Arial;font-size:13px; color: rgba(0,0,0,1.0); margin: 0px; line-height: auto;">Jon,</div><div id="bloop_customfont" style="font-family:Helvetica,Arial;font-size:13px; color: rgba(0,0,0,1.0); margin: 0px; line-height: auto;"><br></div><div id="bloop_customfont" style="font-family:Helvetica,Arial;font-size:13px; color: rgba(0,0,0,1.0); margin: 0px; line-height: auto;">Inline.</div> <br><p class="airmail_on" style="color:#000;">On June 18, 2015 at 1:22:47 PM, Jon Masamitsu (<a href="mailto:jon.masamitsu@oracle.com">jon.masamitsu@oracle.com</a>) wrote:</p> <div><blockquote type="cite" class="clean_bq" style="color: rgb(0, 0, 0); font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;"><span><div bgcolor="#FFFFFF" text="#000000"><div></div><div><br><br><div class="moz-cite-prefix">On 06/18/2015 06:27 AM, Tony Printezis wrote:<br></div><blockquote cite="mid:etPan.5582c73a.34c1b65a.1215a@tw-mbp-tprintezis" type="cite"><div id="bloop_customfont" style="font-family: Helvetica, Arial; font-size: 13px; color: rgb(0, 0, 0); margin: 0px;">Hi Jon,</div><div id="bloop_customfont" style="font-family: Helvetica, Arial; font-size: 13px; color: rgb(0, 0, 0); margin: 0px;"><br></div><div id="bloop_customfont" style="font-family: Helvetica, Arial; font-size: 13px; color: rgb(0, 0, 0); margin: 0px;">Thanks for looking at it. I can definitely add an additional bool flag to turn it on or off. I think it will also make sense to make it manageable so that we can switch the auto-tuning on / off dynamically, if necessary.</div></blockquote><br>Thanks.<br><br>When you were doing the performance testing, did you have some type of logging<br>so that you could see the cards-per-stride-chunk that was being used? <span class="Apple-converted-space"> </span></div></div></span></blockquote></div><p><br></p><p>Yes, I had ad-hoc output for that.</p><p><br></p><div><div><blockquote type="cite" class="clean_bq" style="color: rgb(0, 0, 0); font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;"><span><div bgcolor="#FFFFFF" text="#000000"><div>Eventually<br>someone is going to ask for it so if you had something succinct I'd be glad to see it<br>included in this push.</div></div></span></blockquote></div><p><br></p><p>I think it’d be helpful, but I’d be apprehensive adding more GC log output that will mess up GC logs even more. :-) Any suggestions on maybe some existing output I could piggy-back this on?</p><p>Tony</p><p><br></p><div><blockquote type="cite" class="clean_bq" style="color: rgb(0, 0, 0); font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;"><span><div bgcolor="#FFFFFF" text="#000000"><div><br>Jon<br><blockquote cite="mid:etPan.5582c73a.34c1b65a.1215a@tw-mbp-tprintezis" type="cite"><div id="bloop_customfont" style="font-family: Helvetica, Arial; font-size: 13px; color: rgb(0, 0, 0); margin: 0px;"><br></div><div id="bloop_customfont" style="font-family: Helvetica, Arial; font-size: 13px; color: rgb(0, 0, 0); margin: 0px;">Tony</div><br><p class="airmail_on" style="color: rgb(0, 0, 0);">On June 17, 2015 at 9:46:16 PM, Jon Masamitsu (<a moz-do-not-send="true" href="mailto:jon.masamitsu@oracle.com">jon.masamitsu@oracle.com</a>) wrote:</p><blockquote type="cite" class="clean_bq"><div bgcolor="#FFFFFF" text="#000000"><div><span>Tony,<br><br>I'm still studying the patch but would you consider a more explicit<br>flag to turn this on and off? What you have is very reasonable but<br>if the performance team sees some regression, it would be easier<br>for them to turn the feature on or off rather than go look for the value<br>of<span class="Apple-converted-space"> </span><span class="new">ParGCCardsPerStrideChunk</span><span class="Apple-converted-space"> </span>that is the default and then put that<br>on the command line. Same would be true for a customer who has<br>an application operating in one of the corners where the performance<br>is worse.<br><br>Jon<br> <br></span><div class="moz-cite-prefix">On 6/17/2015 3:30 PM, Tony Printezis wrote:<br></div><blockquote cite="mid:etPan.5581f51b.699a1ea0.1215a@tw-mbp-tprintezis" type="cite"><div id="bloop_customfont" style="font-family: Helvetica, Arial; font-size: 13px; color: rgb(0, 0, 0); margin: 0px;">Hi all,</div><div id="bloop_customfont" style="font-family: Helvetica, Arial; font-size: 13px; color: rgb(0, 0, 0); margin: 0px;"><br></div><div id="bloop_customfont" style="font-family: Helvetica, Arial; font-size: 13px; color: rgb(0, 0, 0); margin: 0px;">A small patch for your consideration:</div><div id="bloop_customfont" style="font-family: Helvetica, Arial; font-size: 13px; color: rgb(0, 0, 0); margin: 0px;"><br></div><div id="bloop_customfont" style="font-family: Helvetica, Arial; font-size: 13px; color: rgb(0, 0, 0); margin: 0px;"><a moz-do-not-send="true" href="http://cr.openjdk.java.net/%7Etonyp/8086056/webrev.0/">http://cr.openjdk.java.net/~tonyp/8086056/webrev.0/</a></div><div id="bloop_customfont" style="font-family: Helvetica, Arial; font-size: 13px; color: rgb(0, 0, 0); margin: 0px;"><br></div><div id="bloop_customfont" style="font-family: Helvetica, Arial; font-size: 13px; color: rgb(0, 0, 0); margin: 0px;">(BTW, for some reason some of the webrev output is a bit messed up. Not sure why, maybe some hg incompatibility I guess. The diffs look OK though. I also attached the patch to this e-mail.)</div><div id="bloop_customfont" style="font-family: Helvetica, Arial; font-size: 13px; color: rgb(0, 0, 0); margin: 0px;"><br></div><div id="bloop_customfont" style="font-family: Helvetica, Arial; font-size: 13px; color: rgb(0, 0, 0); margin: 0px;">There’s a bit of info on the JIRA on the rationale for the patch:</div><div id="bloop_customfont" style="font-family: Helvetica, Arial; font-size: 13px; color: rgb(0, 0, 0); margin: 0px;"><br></div><div id="bloop_customfont" style="font-family: Helvetica, Arial; font-size: 13px; color: rgb(0, 0, 0); margin: 0px;"><a moz-do-not-send="true" href="https://bugs.openjdk.java.net/browse/JDK-8086056">https://bugs.openjdk.java.net/browse/JDK-8086056</a></div><div id="bloop_customfont" style="font-family: Helvetica, Arial; font-size: 13px; color: rgb(0, 0, 0); margin: 0px;"><br></div><div id="bloop_customfont" style="font-family: Helvetica, Arial; font-size: 13px; color: rgb(0, 0, 0); margin: 0px;">The min / max values for the old gen capacity and ParGCCardsPerStrideChunk were chosen empircally after running a few (mostly synthetic tests) on Linux x64. If someone has the cycles to do a more extensive performance study, I’d be happy to revise them accordingly.</div><div id="bloop_customfont" style="font-family: Helvetica, Arial; font-size: 13px; color: rgb(0, 0, 0); margin: 0px;"><br></div><div id="bloop_customfont" style="font-family: Helvetica, Arial; font-size: 13px; color: rgb(0, 0, 0); margin: 0px;">Regards,</div><div id="bloop_customfont" style="font-family: Helvetica, Arial; font-size: 13px; color: rgb(0, 0, 0); margin: 0px;"><br></div><div id="bloop_customfont" style="font-family: Helvetica, Arial; font-size: 13px; color: rgb(0, 0, 0); margin: 0px;">Tony</div><br><div id="bloop_sign_1434579909530055936" class="bloop_sign"><div style="font-family: helvetica, arial; font-size: 13px;"><div>-----</div><div><br></div><div>Tony Printezis | JVM/GC Engineer / VM Team | Twitter</div><div><br></div><div>@TonyPrintezis</div><div><a moz-do-not-send="true" href="mailto:tprintezis@twitter.com">tprintezis@twitter.com</a></div><div><br></div></div></div></blockquote><br></div></div></blockquote><div id="bloop_sign_1434633343182564864" class="bloop_sign"><div style="font-family: helvetica, arial; font-size: 13px;"><div>-----</div><div><br></div><div>Tony Printezis | JVM/GC Engineer / VM Team | Twitter</div><div><br></div><div>@TonyPrintezis</div><div><a moz-do-not-send="true" href="mailto:tprintezis@twitter.com">tprintezis@twitter.com</a></div><div><br></div></div></div></blockquote><br></div></div></span></blockquote><br class="Apple-interchange-newline"></div><br class="Apple-interchange-newline"></div> <div id="bloop_sign_1434652180236058112" class="bloop_sign"><div style="font-family:helvetica,arial;font-size:13px"><div>-----</div><div><br></div><div>Tony Printezis | JVM/GC Engineer / VM Team | Twitter</div><div><br></div><div>@TonyPrintezis</div><div><a href="mailto:tprintezis@twitter.com">tprintezis@twitter.com</a></div><div><br></div></div></div></body></html>