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    <div class="moz-cite-prefix">On 06/18/2015 06:27 AM, Tony Printezis
      wrote:<br>
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    <blockquote
      cite="mid:etPan.5582c73a.34c1b65a.1215a@tw-mbp-tprintezis"
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        rgba(0,0,0,1.0); margin: 0px; line-height: auto;">Hi Jon,</div>
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        style="font-family:Helvetica,Arial;font-size:13px; color:
        rgba(0,0,0,1.0); margin: 0px; line-height: auto;">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>
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    <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?   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.<br>
    <br>
    Jon<br>
    <blockquote
      cite="mid:etPan.5582c73a.34c1b65a.1215a@tw-mbp-tprintezis"
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      <br>
      <p class="airmail_on" style="color:#000;">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>
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              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="new">ParGCCardsPerStrideChunk</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>
              <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">
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                  Hi all,</div>
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                  A small patch for your consideration:</div>
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                  <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>
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                  (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>
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                  There’s a bit of info on the JIRA on the rationale for
                  the
                  patch:</div>
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                  <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>
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                  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>
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                  Regards,</div>
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                  Tony</div>
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                    <div>-----</div>
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                    <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>
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          <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>
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