[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] Re: [Xen-devel] [PATCH v8 00/10] qspinlock: a 4-byte queue spinlock with PV support
On 04/07/2014 01:51 PM, Raghavendra K T wrote: On 04/07/2014 10:08 PM, Waiman Long wrote:On 04/07/2014 02:14 AM, Raghavendra K T wrote:[...]But I am seeing hang in overcommit cases. Gdb showed that many vcpus are halted and there was no progress. Suspecting the problem /race with halting, I removed the halt() part of kvm_hibernate(). I am yet to take a closer look at the code on halt() related changes.It seems like there may still be race conditions where the current code is not handling correctly. I will look into that to see where the problem is. BTW, what test do you use to produce the hang condition?Running ebizzy on 2 of the vms simultaneously (for sometime in repeated loop) could reproduce it. Yes, I am able to reproduce the hang problem with ebizzy. BTW, could you try to apply the attached patch file on top of the v8 patch series to see if it can fix the hang problem? What is the baseline for the performance improvement? Is it without the unfair lock and PV qspinlock?Baseline was 3.14-rc8 without any of the qspin patch series. Does the baseline have PV ticketlock or without any PV support? -Longman Attachment:
0011 _______________________________________________ Xen-devel mailing list Xen-devel@xxxxxxxxxxxxx http://lists.xen.org/xen-devel
|
Lists.xenproject.org is hosted with RackSpace, monitoring our |