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<p>Right, with Ramki's suggestion to use `-XX:+SafepointTimeout` it will log a warning with the status of only the threads that haven't reached the safepoint. There'd be no need to change the -Xlog configuration as I suggested earlier. Note, the default value
for `XX:<span>SafepointTimeoutDelay` is 10 seconds. </span></p>
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<p><span></span>There is also a flag: `-XX:+<span>AbortVMOnSafepointTimeout` that will terminate the JVM when a safepoint isn't reached before the timeout. This may be preferable to leaving the instance in an unresponsive state? <span style="font-family:Calibri,Helvetica,sans-serif,EmojiFont,"Apple Color Emoji","Segoe UI Emoji",NotoColorEmoji,"Segoe UI Symbol","Android Emoji",EmojiSymbols; font-size:16px"><span style="font-family:Calibri,Helvetica,sans-serif,EmojiFont,"Apple Color Emoji","Segoe UI Emoji",NotoColorEmoji,"Segoe UI Symbol","Android Emoji",EmojiSymbols; font-size:16px"></span></span></span></p>
<p><span><br>
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<p><span>William</span></p>
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<div id="x_divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" color="#000000" style="font-size:11pt"><b>From:</b> Kirill A.Korinsky <kirill@korins.ky><br>
<b>Sent:</b> Friday, January 19, 2024 2:00:35 PM<br>
<b>To:</b> Kemper, William<br>
<b>Cc:</b> Ramakrishna, Ramki; shenandoah-dev@openjdk.org<br>
<b>Subject:</b> RE: [EXTERNAL] shenandoah-dev Digest, Vol 100, Issue 40</font>
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<div class="PlainText">CAUTION: This email originated from outside of the organization. Do not click links or open attachments unless you can confirm the sender and know the content is safe.<br>
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On Fri, 19 Jan 2024 22:43:46 +0100,<br>
Kemper, William wrote:<br>
><br>
> It's not a true deadlock. The VMThread is in a busy loop checking if other<br>
> threads have finished. The SafepointTimeout is checked during execution of the<br>
> VMThread's busy/wait loop. See<br>
> <a href="https://github.com/openjdk/jdk17u-dev/blob/master/src/hotspot/share/runtime/safepoint.cpp#L250">
https://github.com/openjdk/jdk17u-dev/blob/master/src/hotspot/share/runtime/safepoint.cpp#L250</a>.<br>
><br>
<br>
Indeed.<br>
<br>
That means I may use something huge like 1 second to avoid almost all logs<br>
except when issue is happened, am I right?<br>
<br>
--<br>
wbr, Kirill<br>
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