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<p class="MsoNormal"><span style="font-size:11.0pt">The title of <a href="https://bugs.openjdk.org/browse/JDK-8366434">
JDK-8366434</a> suggests the issue only affects G1, but I find it also affects ParallelGC:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:10.0pt;font-family:"Courier New"">$ "${OPENJDK_DIR}"/</span>
<span style="font-size:10.0pt;font-family:"Courier New"">jdk-25.0.1/bin/java -showversion -XX:+UseParallelGC -XX:+UseTransparentHugePages -Xms12g -Xmx12g -Xlog:pagesize=info -cp ~/Play/Java HelloWorld<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] Explicit hugepage support:<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] hugepage size: 2M<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] hugepage size: 512M<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] hugepage size: 16G<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] default hugepage size: 512M<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] Transparent hugepage (THP) support:<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize]
<span style="background:yellow;mso-highlight:yellow">THP mode: always</span><o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize]
<span style="background:yellow;mso-highlight:yellow">THP pagesize: 512M</span><o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] Shared memory transparent hugepage (THP) support:<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] Shared memory THP mode: never<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] JVM will attempt to prevent THPs in thread stacks.<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] UseLargePages=1, UseTransparentHugePages=1<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] Large page support enabled. Usable page sizes: 64k, 512M.
<span style="background:yellow;mso-highlight:yellow">Default large page size: 512M</span>.<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.002s][info][pagesize] CodeHeap 'profiled nmethods': min=2496K max=118272K base=0x00004000108d0000 size=118272K page_size=64K<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.002s][info][pagesize] CodeHeap 'non-nmethods': min=2496K max=9152K base=0x0000400017c50000 size=9152K page_size=64K<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.002s][info][pagesize] CodeHeap 'non-profiled nmethods': min=2496K max=118336K base=0x0000400018540000 size=118336K page_size=64K<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.002s][info][pagesize]
<span style="background:yellow;mso-highlight:yellow">Heap: min=12G max=12G base=0x0000000500000000 size=12G page_size=64K</span><o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.002s][info][pagesize] Card Table: min=24M max=24M base=0x0000400001ee0000 size=24M page_size=64K<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.004s][info][pagesize] Mark Bitmap: min=192M max=192M base=0x0000400025000000 size=192M page_size=64K<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.004s][info][pagesize] Parallel Compact Data: min=960K max=960K base=0x00004000038f0000 size=960K page_size=64K<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:10.0pt;font-family:"Courier New"">openjdk version "25.0.1" 2025-10-21<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:10.0pt;font-family:"Courier New"">OpenJDK Runtime Environment (build 25.0.1+8-27)<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:10.0pt;font-family:"Courier New"">OpenJDK 64-Bit Server VM (build 25.0.1+8-27, mixed mode, sharing)<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:10.0pt;font-family:"Courier New"">Hello world!</span><span style="font-size:11.0pt"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">The <a href="https://bugs.openjdk.org/browse/JDK-8366564">
Release Note</a> says<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:10.5pt;font-family:"Segoe UI",sans-serif;color:#172B4D;background:white">A workaround to allow the use of transparent huge pages with G1 is to configure the THP mode as `always`:</span><span style="font-size:10.5pt;font-family:"Segoe UI",sans-serif;color:#172B4D"><br>
<span style="background:white">```</span><br>
<span style="background:white"># echo always > /sys/kernel/mm/transparent_hugepage/enabled</span><br>
<span style="background:white">```<o:p></o:p></span></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">but I observe the issue (see above) even though my system has transparent huge pages configured to "always":<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:10.0pt;font-family:"Courier New"">$ cat /sys/kernel/mm/transparent_hugepage/enabled<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:10.0pt;font-family:"Courier New"">[always] madvise never<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">It looks like <a href="https://github.com/openjdk/jdk25u/commit/a66fe2a8765c085b8faeb9c89751306b834935ce">
code changes</a> affect code shared by all (?) the collectors, so a fix for G1GC probably fixes ParallelGC, even if the description only covers G1G1. The tests in there seem capable of testing SerialGC, ParallelGC, and G1GC, so that is reassuring.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">I will wait patiently for JDK 25.0.2.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> ... peter<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<div style="border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in">
<p class="MsoNormal" style="margin-left:.5in"><b><span style="font-family:"Calibri",sans-serif;color:black">From:
</span></b><span style="font-family:"Calibri",sans-serif;color:black">Stefan Johansson <stefan.johansson@oracle.com><br>
<b>Date: </b>Tuesday, November 4, 2025 at 01:38<br>
<b>To: </b>Peter Kessler OS <peter.kessler@os.amperecomputing.com>, "hotspot-gc-use@openjdk.java.net" <hotspot-gc-use@openjdk.java.net><br>
<b>Subject: </b>Re: Wither transparent huge pages for the heap?</span><span style="font-family:"Calibri",sans-serif;color:black;mso-ligatures:none"><o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal" style="margin-left:.5in"><o:p> </o:p></p>
</div>
<p class="MsoNormal" style="mso-margin-top-alt:0in;margin-right:0in;margin-bottom:12.0pt;margin-left:.5in">
Hi Peter,<br>
<br>
This is a known issue [1], and we found the problem a bit to late for the fix to be included in the initial release of JDK 25. See the JBS issue [2] for more details.<br>
<br>
The fix for the problem is scheduled to be released in JDK 25.0.2. The workaround (which is not optimal) is to configure the THP mode to 'always' in:<br>
/sys/kernel/mm/transparent_hugepage/enabled<br>
<br>
This will make the heap be backed by transparent huge pages. When configured as 'always' you don't need the -XX:+UseTransparentHugePages flag. The logs won't reflect the actual page size used if I'm not mistaken, but you can use OS tools to verify that transparent
huge pages are used for the heap.<br>
<br>
Hope this helps,<br>
Stefan<br>
<br>
[1] <a href="https://www.oracle.com/java/technologies/javase/25-relnote-issues.html">
https://www.oracle.com/java/technologies/javase/25-relnote-issues.html</a><br>
[2] <a href="https://bugs.openjdk.org/browse/JDK-8366434">https://bugs.openjdk.org/browse/JDK-8366434</a><o:p></o:p></p>
<div>
<p class="MsoNormal" style="margin-left:.5in">On 2025-11-03 21:55, Peter Kessler OS wrote:<o:p></o:p></p>
</div>
<blockquote style="margin-top:5.0pt;margin-bottom:5.0pt">
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:11.0pt">Between JDK-24 (24.0.2+12-54, dba 24.0.2) and JDK-25 (25.0.1+8-27, dba 25.0.1), running an application on a machine with 64KiB system page size and 512MiB transparent huge pages, I
see this difference:</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:11.0pt"> </span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">$ "${OPENJDK_DIR}"/jdk-24.0.2/bin/java -showversion
<span style="background:yellow;mso-highlight:yellow">-XX:+UseTransparentHugePages</span> -Xmx12g -Xms12g -Xlog:pagesize=info HelloWorld</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] Explicit hugepage support:</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] hugepage size: 2M</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] hugepage size: 512M</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] hugepage size: 16G</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] default hugepage size: 512M</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] Transparent hugepage (THP) support:</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] THP mode: always</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] THP pagesize: 512M</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] Shared memory transparent hugepage (THP) support:</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] Shared memory THP mode: never</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] JVM will attempt to prevent THPs in thread stacks.</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] UseLargePages=1, UseTransparentHugePages=1</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] Large page support enabled. Usable page sizes: 64k, 512M. Default large page size: 512M.</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.002s][info][pagesize] CodeHeap 'profiled nmethods': min=2496K max=118272K base=0x00004000108d0000 size=118272K page_size=64K</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.002s][info][pagesize] CodeHeap 'non-nmethods': min=2496K max=9152K base=0x0000400017c50000 size=9152K page_size=64K</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.002s][info][pagesize] CodeHeap 'non-profiled nmethods': min=2496K max=118336K base=0x0000400018540000 size=118336K page_size=64K</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.003s][info][pagesize] Heap: min=12G max=12G base=0x0000000500000000 size=12G
<span style="background:yellow;mso-highlight:yellow">page_size=512M</span></span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.003s][info][pagesize] Block Offset Table: req_size=24M req_page_size=64K base=0x0000400024440000 size=24M page_size=64K</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.003s][info][pagesize] Card Table: req_size=24M req_page_size=64K base=0x0000400025c40000 size=24M page_size=64K</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.003s][info][pagesize] Mark Bitmap: req_size=192M req_page_size=64K base=0x0000400027440000 size=192M page_size=64K</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">openjdk version "24.0.2" 2025-07-15</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">OpenJDK Runtime Environment (build 24.0.2+12-54)</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">OpenJDK 64-Bit Server VM (build 24.0.2+12-54, mixed mode, sharing)</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">Hello world!</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:11.0pt"> </span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:11.0pt">versus</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:11.0pt"> </span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">$ "${OPENJDK_DIR}"/jdk-25.0.1/bin/java -showversion
<span style="background:yellow;mso-highlight:yellow">-XX:+UseTransparentHugePages</span> -Xmx12g -Xms12g -Xlog:pagesize=info HelloWorld</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] Explicit hugepage support:</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] hugepage size: 2M</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] hugepage size: 512M</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] hugepage size: 16G</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] default hugepage size: 512M</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] Transparent hugepage (THP) support:</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] THP mode: always</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] THP pagesize: 512M</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] Shared memory transparent hugepage (THP) support:</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] Shared memory THP mode: never</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] JVM will attempt to prevent THPs in thread stacks.</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] UseLargePages=1, UseTransparentHugePages=1</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.001s][info][pagesize] Large page support enabled. Usable page sizes: 64k, 512M. Default large page size: 512M.</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.002s][info][pagesize] CodeHeap 'profiled nmethods': min=2496K max=118272K base=0x00004000108d0000 size=118272K page_size=64K</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.002s][info][pagesize] CodeHeap 'non-nmethods': min=2496K max=9152K base=0x0000400017c50000 size=9152K page_size=64K</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.002s][info][pagesize] CodeHeap 'non-profiled nmethods': min=2496K max=118336K base=0x0000400018540000 size=118336K page_size=64K</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.003s][info][pagesize] Heap: min=12G max=12G base=0x0000000500000000 size=12G
<span style="background:yellow;mso-highlight:yellow">page_size=64K</span></span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.003s][info][pagesize] Block Offset Table: req_size=24M req_page_size=64K base=0x0000400024550000 size=24M page_size=64K</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.003s][info][pagesize] Card Table: req_size=24M req_page_size=64K base=0x0000400025d50000 size=24M page_size=64K</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">[0.003s][info][pagesize] Mark Bitmap: req_size=192M req_page_size=64K base=0x0000400027550000 size=192M page_size=64K</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">openjdk version "25.0.1" 2025-10-21</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">OpenJDK Runtime Environment (build 25.0.1+8-27)</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">OpenJDK 64-Bit Server VM (build 25.0.1+8-27, mixed mode, sharing)</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"><span style="font-size:10.0pt;font-family:"Courier New"">Hello world!</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:11.0pt"> </span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:11.0pt">Why am I not getting 512MiB pages for my heap in JDK-25, when I was getting 512MiB pages for my heap in JDK-24? Maybe more to the point: How do I get transparent huge pages for my
heap in JDK-25?</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:11.0pt"> </span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:11.0pt"> ... peter</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="mso-ligatures:none"><br>
<br>
<o:p></o:p></span></p>
<pre style="margin-left:.5in">_______________________________________________<o:p></o:p></pre>
<pre style="margin-left:.5in">hotspot-gc-use mailing list<o:p></o:p></pre>
<pre style="margin-left:.5in"><a href="mailto:hotspot-gc-use@openjdk.org">hotspot-gc-use@openjdk.org</a><o:p></o:p></pre>
<pre style="margin-left:.5in"><a href="https://mail.openjdk.org/mailman/listinfo/hotspot-gc-use">https://mail.openjdk.org/mailman/listinfo/hotspot-gc-use</a><o:p></o:p></pre>
</blockquote>
<p class="MsoNormal" style="margin-left:.5in"><span style="mso-ligatures:none"><br>
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