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Yes, this happens on multi machines but only on those with a specific disk driver. I am thinking the device drivers which runs in kernel mode could corrupt other's memory. The smartctl is kicked off by command line which makes system call by issuing ioctl like
what I copy & pasted in last email. </div>
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No, we don't swap to disk. </div>
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There is one question I would need help before I starting investigation. When a device driver servicing one user mode application's system call(ioctl), can that device driver corrupt other user mode application's memory(heap in our case)? How? </div>
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<p>发送自 <a href="http://aka.ms/weboutlook">Outlook</a><br>
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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 10:03<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: 回复: JVM crashes constantly when High GC happens</font>
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<div class="PlainText">On 4/23/19 3:16 PM, shang xinli wrote:<br>
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> Thanks, Andrew! I agree it could be because of memory corruption.<br>
> The issue only reproduced when a tool smartctl is kicked off.<br>
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More information needed.<br>
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Does this happen on moe than one machine?<br>
How is smartctl kicked off? What commands does it use? Are you<br>
swapping onto this disk?<br>
<br>
> It has system call as below. Do you think it is possible that the<br>
> device driver corrupts JVM's memory? How do I start investigating?<br>
> Any use tool?<br>
<br>
It's going to be extremely difficult. I'm thinking about kernel bugs. Is<br>
your kernel up to date? All the device drivers?<br>
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-- <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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