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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Greetings,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I am continuing the earlier discussion [1] with a revised issue number representing the implementation of the JEP [2].<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I have addressed the remaining unaddressed comments (copied below) in these webrevs -<o:p></o:p></p>
<p class="MsoNormal"><a href="http://cr.openjdk.java.net/~kkharbas/8190308/webrev.11/">http://cr.openjdk.java.net/~kkharbas/8190308/webrev.11/</a><o:p></o:p></p>
<p class="MsoNormal"><a href="http://cr.openjdk.java.net/~kkharbas/8190308/webrev.11_to_10/">http://cr.openjdk.java.net/~kkharbas/8190308/webrev.11_to_10/</a><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Also, I would appreciate a review of the CSR for the new flag at
<a href="https://bugs.openjdk.java.net/browse/JDK-8190309">https://bugs.openjdk.java.net/browse/JDK-8190309</a>.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoPlainText">> > - in that same thread there has also been the question about the<o:p></o:p></p>
<p class="MsoPlainText">> > need <o:p></o:p></p>
<p class="MsoPlainText">> > for blocking the signals for the process that has gone unanswered.<o:p></o:p></p>
<p class="MsoPlainText">> > <o:p></o:p></p>
<p class="MsoPlainText"><o:p> </o:p></p>
<p class="MsoPlainText">Removed the blocking of signals.<o:p></o:p></p>
<p class="MsoPlainText"><o:p> </o:p></p>
<p class="MsoPlainText">> > - Arguments::finalize_vm_init_args: maybe at the place where the <o:p></o:p></p>
<p class="MsoPlainText">> > change adds the warning/info message about NUMA support being<o:p></o:p></p>
<p class="MsoPlainText">> > specific <o:p></o:p></p>
<p class="MsoPlainText">> > to the file system; also add the same warning about UseLargePages<o:p></o:p></p>
<p class="MsoPlainText">> > that <o:p></o:p></p>
<p class="MsoPlainText">> > is located elsewhere.<o:p></o:p></p>
<p class="MsoPlainText">> > <o:p></o:p></p>
<p class="MsoPlainText">> > Like "UseXXXX may not be supported in some specific file system <o:p></o:p></p>
<p class="MsoPlainText">> > implementations." - or just ignore as Andrew said in the other<o:p></o:p></p>
<p class="MsoPlainText">> > email thread.<o:p></o:p></p>
<p class="MsoPlainText">> > <o:p></o:p></p>
<p class="MsoPlainText">> > Note that I am not sure that the selected place is the correct<o:p></o:p></p>
<p class="MsoPlainText">> > place <o:p></o:p></p>
<p class="MsoPlainText">> > for such warning about incompatible flags (and maybe <o:p></o:p></p>
<p class="MsoPlainText">> > UseNUMA/UseLargePages should be forcibly disabled here? But then <o:p></o:p></p>
<p class="MsoPlainText">> > again, it does not hurt just having it enabled?).<o:p></o:p></p>
<p class="MsoPlainText">> > <o:p></o:p></p>
<p class="MsoPlainText">> > I will let the runtime team comment as a lot of that argument <o:p></o:p></p>
<p class="MsoPlainText">> > processing changed in jdk9.<o:p></o:p></p>
<p class="MsoPlainText">> > <o:p></o:p></p>
<p class="MsoPlainText">> > Maybe Arguments::check_vm_args_consistency() is better.<o:p></o:p></p>
<p class="MsoPlainText">> > <o:p></o:p></p>
<p class="MsoPlainText">> > There is similar code in Arguments::adjust_after_os()...<o:p></o:p></p>
<p class="MsoPlainText">> > <o:p></o:p></p>
<p class="MsoPlainText"><o:p> </o:p></p>
<p class="MsoPlainText">1. Moved the check from finalize_vm_init_args() <span style="font-size:9.5pt;font-family:Consolas">
to </span>check_vm_args_consistency()<o:p></o:p></p>
<p class="MsoPlainText">2. When UseNUMA flag is true, adaptive logical group chunk resizing is used for Numa aware collectors such as ParallelOld. Just like UseNUMA is disabled in os::inti_2() in Linux when UseLargePages is set, it will be a good idea to disable
UseNUMA when the new option is used.<o:p></o:p></p>
<p class="MsoPlainText">3. I think its ok to leave UseNUMAInterleaving ON as it can be used for other memory areas.<o:p></o:p></p>
<p class="MsoPlainText">4. For the same reason I also do not disable UseLargePages.<o:p></o:p></p>
<p class="MsoPlainText">5. About handling UseLargePages, I thought of handling it the same way as when reserve_memory_special() fails to allocate large pages, i.e. generating a log_debug message.
<o:p></o:p></p>
<p class="MsoPlainText" style="margin-left:1.0in"> <i><span style="font-family:"Courier New"">// failed; try to reserve regular memory below</span></i><o:p></o:p></p>
<p class="MsoPlainText" style="margin-left:1.0in"><i><span style="font-family:"Courier New""> if (UseLargePages && (!FLAG_IS_DEFAULT(UseLargePages) ||</span></i><o:p></o:p></p>
<p class="MsoPlainText" style="margin-left:1.0in"><i><span style="font-family:"Courier New""> !FLAG_IS_DEFAULT(LargePageSizeInBytes))) {</span></i><o:p></o:p></p>
<p class="MsoPlainText" style="margin-left:1.0in"><i><span style="font-family:"Courier New""> log_debug(gc, heap, coops)("Reserve regular memory without large pages");</span></i><o:p></o:p></p>
<p class="MsoPlainText"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoPlainText">> > - here I may probably be speaking wrongly on behalf of the<o:p></o:p></p>
<p class="MsoPlainText">> > runtime <o:p></o:p></p>
<p class="MsoPlainText">> > team, but os.hpp, as an abstraction of the OS should probably not<o:p></o:p></p>
<p class="MsoPlainText">> > have <o:p></o:p></p>
<p class="MsoPlainText">> > platform specific ifdefs in it.<o:p></o:p></p>
<p class="MsoPlainText">> > <o:p></o:p></p>
<p class="MsoNormal">and <o:p></o:p></p>
<p class="MsoPlainText">> > > - You removed os::attempt_reserve_memory_at() from os.cpp and<o:p></o:p></p>
<p class="MsoPlainText">> > > split <o:p></o:p></p>
<p class="MsoPlainText">> > > into os_posix.cpp and os_windows.cpp.<o:p></o:p></p>
<p class="MsoPlainText">> > > But I think you should remain os::attempt_reserve_memory_at()<o:p></o:p></p>
<p class="MsoPlainText">> > > at <o:p></o:p></p>
<p class="MsoPlainText">> > > os.cpp and implement os specific stuffs at each os_xxx.cpp files<o:p></o:p></p>
<p class="MsoPlainText">> > > for <o:p></o:p></p>
<p class="MsoPlainText">> > > pd_xxx. Of cource move MemTracker function call as well.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoPlainText">In the updated webrev, I move the implementation from os_posix.cpp and os_window.cpp to respective pd_xxx functions. No AIX specific ifdef is required now.<o:p></o:p></p>
<p class="MsoPlainText"><o:p> </o:p></p>
<p class="MsoPlainText"><o:p> </o:p></p>
<p class="MsoPlainText">Thank you and looking forward for your feedback.<o:p></o:p></p>
<p class="MsoPlainText">- Kishor<o:p></o:p></p>
<p class="MsoPlainText"><o:p> </o:p></p>
<p class="MsoNormal">[1] <a href="http://mail.openjdk.java.net/pipermail/hotspot-gc-dev/2017-October/020682.html">
http://mail.openjdk.java.net/pipermail/hotspot-gc-dev/2017-October/020682.html</a><o:p></o:p></p>
<p class="MsoNormal">[2] <a href="https://bugs.openjdk.java.net/browse/JDK-8171181">
https://bugs.openjdk.java.net/browse/JDK-8171181</a><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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