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Thanks, Andrew! I agree it could be because of memory corruption. The issue only reproduced when a tool smartctl is kicked off. It has system call as below. Do you think it is possible that the device driver corrupts JVM's memory? How do I start investigating?
Any use tool? </div>
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<pre style="margin: 0px; padding: 12px; background: rgba(71, 87, 120, 0.08); display: block; overflow: auto; border-radius: 3px; font: 400 11px/15px Menlo, Consolas, Monaco, monospace; text-align: left">ioctl(3, SG_IO, {'S', SG_DXFER_FROM_DEV, cmd[16]=[85, 09, 0e, 00, 00, 00, 40, 00, 03, 00, 00, 00, 00, 00, 2f, 00], mx_sb_len=32, iovec_count=0, dxfer_len=32768, timeout=20000, flags=0, data[32768]=["\1\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"...], status=00, masked_status=00, sb[0]=[], host_status=0, driver_status=0, resid=0, duration=5024, info=0}) = 0</pre>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" color="#000000" style="font-size:11pt"><b>发件人:</b> Andrew Haley <aph@redhat.com><br>
<b>发送时间:</b> 2019年4月23日 3:15<br>
<b>收件人:</b> shang xinli; Kim Barrett; shade@redhat.com<br>
<b>抄送:</b> hotspot-gc-dev@openjdk.java.net<br>
<b>主题:</b> Re: 回复: 回复: JVM crashes constantly when High GC happens</font>
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<div class="PlainText">On 4/19/19 11:08 PM, shang xinli wrote:<br>
> I just reproduced it with the fastdebug build. Now it reports error at PromotionInfo:verify(). More specifically, it found numDisplaceHdrs NOT equal numObjWithDisplaceHdrs. It fails at below.<br>
> <br>
> <br>
> guarantee(numDisplacedHdrs == numObjsWithDisplacedHdrs, "Displaced hdr count”);<br>
> <br>
> Here is the debug info. It would be great if somebody can help to<br>
> guide how to instrument the code to find out the root cause.<br>
<br>
There's no recipe that you can use here.<br>
<br>
A displaced header occurs when an object is locked, so the object's<br>
first word (with tag bits, etc.) is copied elswhere and replaced in<br>
the object by a pointer to a structure. Displaced headers fairly<br>
uncommon: it only happens when there is contention for a lock and a<br>
thread is blocked. When a GC does its marking phase, it has to keep<br>
track of displaced headers.<br>
<br>
You do not have a bug in the GC. The problem is memory corruption. Are<br>
you using any native libraries? That is where I would start.<br>
<br>
-- <br>
Andrew Haley<br>
Java Platform Lead Engineer<br>
Red Hat UK Ltd. <<a href="https://www.redhat.com">https://www.redhat.com</a>><br>
EAC8 43EB D3EF DB98 CC77 2FAD A5CD 6035 332F A671<br>
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