Bugs item #2494730, was opened at 2009-01-09 09:59 Message generated for change (Tracker Item Submitted) made by Item Submitter You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=893831&aid=2494730&group_id=180599
Please note that this message will contain a full copy of the comment thread, including the initial issue submission, for this request, not just the latest update. Category: None Group: None Status: Open Resolution: None Priority: 5 Private: No Submitted By: Kevin Shanahan (kmshanah) Assigned to: Nobody/Anonymous (nobody) Summary: Guests "stalling" on kvm-82 Initial Comment: I am seeing periodic stalls in Linux and Windows guests with kvm-82 on an IBM X3550 server with 2 x Xeon 5130 CPUs and 32GB RAM. I am *reasonably* certain that this is a regression somewhere between kvm-72 and kvm-82. We had been running kvm-72 (actually, the debian kvm-source package) up until now and never noticed the problem. Now the stalls are very obvious. When the guest stalls, the at least one kvm process on the host gobbles up 100% CPU. I'll do my debugging with the Linux guest, as that's sure to be easier to deal with. As a simple demostration that the guest is unresponsive, here is the result of me pinging the guest from another machine on the (very quiet) LAN: --- hermes-old.wumi.org.au ping statistics --- 600 packets transmitted, 600 received, 0% packet loss, time 599659ms rtt min/avg/max/mdev = 0.255/181.211/6291.871/558.706 ms, pipe 7 The latency varies pretty badly, with spikes up to several seconds as you can see. The problem is not reproducable on other VT capable hardware that I have - e.g. my desktop has a E8400 CPU which runs the VMs just fine. Does knowing that make it any easier to guess where the problem might be? The Xeon 5130 does not have the "smx", "est", "sse4_1", "xsave", "vnmi" and "flexpriority" CPU flags that the E8400 does. Because this server is the only hardware I have which exhibits the problem and it's a production machine, I have limited times where I can do testing. However, I will try confirm that kvm-72 is okay and then bisect. Currently the host is running a 2.6.28 kernel with the kvm-82 modules. I guess I'm likely to have problems compiling the older kvm releases against this kernel, so I'll have to drop back to 2.6.27.something to run the tests. CPU Vendor: Intel CPU Type: Xeon 5130 Number of CPUs: 2 Host distribution: Debain Lenny/Sid KVM version: kvm-82 Host kernel: Linux 2.6.28 x86_64 Guest Distribution: Debian Etch Guest kernel: Linux 2.6.27.10 i686 Host's /proc/cpuinfo: processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 15 model name : Intel(R) Xeon(R) CPU 5130 @ 2.00GHz stepping : 6 cpu MHz : 1995.117 cache size : 4096 KB physical id : 0 siblings : 2 core id : 0 cpu cores : 2 apicid : 0 initial apicid : 0 fpu : yes fpu_exception : yes cpuid level : 10 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx lm constant_tsc arch_perfmon pebs bts rep_good pni dtes64 monitor ds_cpl vmx tm2 ssse3 cx16 xtpr pdcm dca lahf_lm tpr_shadow bogomips : 3990.23 clflush size : 64 cache_alignment : 64 address sizes : 36 bits physical, 48 bits virtual power management: processor : 1 vendor_id : GenuineIntel cpu family : 6 model : 15 model name : Intel(R) Xeon(R) CPU 5130 @ 2.00GHz stepping : 6 cpu MHz : 1995.117 cache size : 4096 KB physical id : 0 siblings : 2 core id : 1 cpu cores : 2 apicid : 1 initial apicid : 1 fpu : yes fpu_exception : yes cpuid level : 10 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx lm constant_tsc arch_perfmon pebs bts rep_good pni dtes64 monitor ds_cpl vmx tm2 ssse3 cx16 xtpr pdcm dca lahf_lm tpr_shadow bogomips : 3989.96 clflush size : 64 cache_alignment : 64 address sizes : 36 bits physical, 48 bits virtual power management: processor : 2 vendor_id : GenuineIntel cpu family : 6 model : 15 model name : Intel(R) Xeon(R) CPU 5130 @ 2.00GHz stepping : 6 cpu MHz : 1995.117 cache size : 4096 KB physical id : 3 siblings : 2 core id : 0 cpu cores : 2 apicid : 6 initial apicid : 6 fpu : yes fpu_exception : yes cpuid level : 10 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx lm constant_tsc arch_perfmon pebs bts rep_good pni dtes64 monitor ds_cpl vmx tm2 ssse3 cx16 xtpr pdcm dca lahf_lm tpr_shadow bogomips : 3990.01 clflush size : 64 cache_alignment : 64 address sizes : 36 bits physical, 48 bits virtual power management: processor : 3 vendor_id : GenuineIntel cpu family : 6 model : 15 model name : Intel(R) Xeon(R) CPU 5130 @ 2.00GHz stepping : 6 cpu MHz : 1995.117 cache size : 4096 KB physical id : 3 siblings : 2 core id : 1 cpu cores : 2 apicid : 7 initial apicid : 7 fpu : yes fpu_exception : yes cpuid level : 10 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx lm constant_tsc arch_perfmon pebs bts rep_good pni dtes64 monitor ds_cpl vmx tm2 ssse3 cx16 xtpr pdcm dca lahf_lm tpr_shadow bogomips : 3990.01 clflush size : 64 cache_alignment : 64 address sizes : 36 bits physical, 48 bits virtual power management: ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=893831&aid=2494730&group_id=180599 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
