We have the exactly same problem on our NUMA systems. The clock of windows 2008 guests sometimes just stops and it becomes slow when you are connected via rdp. After connecting to qemu's vnc server everything runs fine again. The problem seems to occour more often when the host is under pressure. What really is weird is that this only happens to the windows 2008 guest. Linux and windows 2003 guests run just fine. We have also only seen the problem on our NUMA hosts, even with cpu and memory pinning. The singel socket servers run the exactly same software without that problem. We have also tried many different configurations on the host(CONFIG_HZ, CONFIG_PREEMTION, CONFIG_NUMA_BALANCING), qemu (different timers, different catchup policies, different spinlock settings) and on the guest side (use platformclock) but none did solve the problem Qemu version: 1.5.3 Linux: 3.11.4 glibc: 2.15 gcc: 4.7.3 # lscpu Architecture: x86_64 CPU op-mode(s): 32-bit, 64-bit Byte Order: Little Endian CPU(s): 24 On-line CPU(s) list: 0-23 Thread(s) per core: 2 Core(s) per socket: 6 Socket(s): 2 NUMA node(s): 2 Vendor ID: GenuineIntel CPU family: 6 Model: 44 Stepping: 2 CPU MHz: 2401.000 BogoMIPS: 4800.18 Virtualization: VT-x L1d cache: 32K L1i cache: 32K L2 cache: 256K L3 cache: 12288K NUMA node0 CPU(s): 0-5,12-17 NUMA node1 CPU(s): 6-11,18-23 # lspci 00:00.0 Host bridge: Intel Corporation 5520 I/O Hub to ESI Port (rev 22) 00:01.0 PCI bridge: Intel Corporation 5520/5500/X58 I/O Hub PCI Express Root Port 1 (rev 22) 00:03.0 PCI bridge: Intel Corporation 5520/5500/X58 I/O Hub PCI Express Root Port 3 (rev 22) 00:05.0 PCI bridge: Intel Corporation 5520/X58 I/O Hub PCI Express Root Port 5 (rev 22) 00:07.0 PCI bridge: Intel Corporation 5520/5500/X58 I/O Hub PCI Express Root Port 7 (rev 22) 00:09.0 PCI bridge: Intel Corporation 7500/5520/5500/X58 I/O Hub PCI Express Root Port 9 (rev 22) 00:0d.0 Host bridge: Intel Corporation Device 343a (rev 22) 00:0d.1 Host bridge: Intel Corporation Device 343b (rev 22) 00:0d.2 Host bridge: Intel Corporation Device 343c (rev 22) 00:0d.3 Host bridge: Intel Corporation Device 343d (rev 22) 00:0d.4 Host bridge: Intel Corporation 7500/5520/5500/X58 Physical Layer Port 0 (rev 22) 00:0d.5 Host bridge: Intel Corporation 7500/5520/5500 Physical Layer Port 1 (rev 22) 00:0d.6 Host bridge: Intel Corporation Device 341a (rev 22) 00:0e.0 Host bridge: Intel Corporation Device 341c (rev 22) 00:0e.1 Host bridge: Intel Corporation Device 341d (rev 22) 00:0e.2 Host bridge: Intel Corporation Device 341e (rev 22) 00:0e.4 Host bridge: Intel Corporation Device 3439 (rev 22) 00:13.0 PIC: Intel Corporation 7500/5520/5500/X58 I/O Hub I/OxAPIC Interrupt Controller (rev 22) 00:14.0 PIC: Intel Corporation 7500/5520/5500/X58 I/O Hub System Management Registers (rev 22) 00:14.1 PIC: Intel Corporation 7500/5520/5500/X58 I/O Hub GPIO and Scratch Pad Registers (rev 22) 00:14.2 PIC: Intel Corporation 7500/5520/5500/X58 I/O Hub Control Status and RAS Registers (rev 22) 00:14.3 PIC: Intel Corporation 7500/5520/5500/X58 I/O Hub Throttle Registers (rev 22) 00:16.0 System peripheral: Intel Corporation 5520/5500/X58 Chipset QuickData Technology Device (rev 22) 00:16.1 System peripheral: Intel Corporation 5520/5500/X58 Chipset QuickData Technology Device (rev 22) 00:16.2 System peripheral: Intel Corporation 5520/5500/X58 Chipset QuickData Technology Device (rev 22) 00:16.3 System peripheral: Intel Corporation 5520/5500/X58 Chipset QuickData Technology Device (rev 22) 00:16.4 System peripheral: Intel Corporation 5520/5500/X58 Chipset QuickData Technology Device (rev 22) 00:16.5 System peripheral: Intel Corporation 5520/5500/X58 Chipset QuickData Technology Device (rev 22) 00:16.6 System peripheral: Intel Corporation 5520/5500/X58 Chipset QuickData Technology Device (rev 22) 00:16.7 System peripheral: Intel Corporation 5520/5500/X58 Chipset QuickData Technology Device (rev 22) 00:1a.0 USB controller: Intel Corporation 82801JI (ICH10 Family) USB UHCI Controller #4 00:1a.1 USB controller: Intel Corporation 82801JI (ICH10 Family) USB UHCI Controller #5 00:1a.2 USB controller: Intel Corporation 82801JI (ICH10 Family) USB UHCI Controller #6 00:1a.7 USB controller: Intel Corporation 82801JI (ICH10 Family) USB2 EHCI Controller #2 00:1c.0 PCI bridge: Intel Corporation 82801JI (ICH10 Family) PCI Express Root Port 1 00:1c.4 PCI bridge: Intel Corporation 82801JI (ICH10 Family) PCI Express Root Port 5 00:1c.5 PCI bridge: Intel Corporation 82801JI (ICH10 Family) PCI Express Root Port 6 00:1d.0 USB controller: Intel Corporation 82801JI (ICH10 Family) USB UHCI Controller #1 00:1d.1 USB controller: Intel Corporation 82801JI (ICH10 Family) USB UHCI Controller #2 00:1d.2 USB controller: Intel Corporation 82801JI (ICH10 Family) USB UHCI Controller #3 00:1d.7 USB controller: Intel Corporation 82801JI (ICH10 Family) USB2 EHCI Controller #1 00:1e.0 PCI bridge: Intel Corporation 82801 PCI Bridge (rev 90) 00:1f.0 ISA bridge: Intel Corporation 82801JIR (ICH10R) LPC Interface Controller 00:1f.2 SATA controller: Intel Corporation 82801JI (ICH10 Family) SATA AHCI Controller 00:1f.3 SMBus: Intel Corporation 82801JI (ICH10 Family) SMBus Controller 01:03.0 VGA compatible controller: Matrox Electronics Systems Ltd. MGA G200eW WPCM450 (rev 0a) 03:00.0 Ethernet controller: Intel Corporation 82574L Gigabit Network Connection 04:00.0 Ethernet controller: Intel Corporation 82574L Gigabit Network Connection 05:00.0 Ethernet controller: Intel Corporation 82599EB 10-Gigabit SFI/SFP+ Network Connection (rev 01) 05:00.1 Ethernet controller: Intel Corporation 82599EB 10-Gigabit SFI/SFP+ Network Connection (rev 01) 08:00.0 RAID bus controller: Adaptec AAC-RAID (rev 09) fe:00.0 Host bridge: Intel Corporation Xeon 5600 Series QuickPath Architecture Generic Non-core Registers (rev 02) fe:00.1 Host bridge: Intel Corporation Xeon 5600 Series QuickPath Architecture System Address Decoder (rev 02) fe:02.0 Host bridge: Intel Corporation Xeon 5600 Series QPI Link 0 (rev 02) fe:02.1 Host bridge: Intel Corporation Xeon 5600 Series QPI Physical 0 (rev 02) fe:02.2 Host bridge: Intel Corporation Xeon 5600 Series Mirror Port Link 0 (rev 02) fe:02.3 Host bridge: Intel Corporation Xeon 5600 Series Mirror Port Link 1 (rev 02) fe:02.4 Host bridge: Intel Corporation Xeon 5600 Series QPI Link 1 (rev 02) fe:02.5 Host bridge: Intel Corporation Xeon 5600 Series QPI Physical 1 (rev 02) fe:03.0 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Registers (rev 02) fe:03.1 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Target Address Decoder (rev 02) fe:03.2 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller RAS Registers (rev 02) fe:03.4 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Test Registers (rev 02) fe:04.0 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 0 Control (rev 02) fe:04.1 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 0 Address (rev 02) fe:04.2 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 0 Rank (rev 02) fe:04.3 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 0 Thermal Control (rev 02) fe:05.0 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 1 Control (rev 02) fe:05.1 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 1 Address (rev 02) fe:05.2 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 1 Rank (rev 02) fe:05.3 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 1 Thermal Control (rev 02) fe:06.0 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 2 Control (rev 02) fe:06.1 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 2 Address (rev 02) fe:06.2 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 2 Rank (rev 02) fe:06.3 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 2 Thermal Control (rev 02) ff:00.0 Host bridge: Intel Corporation Xeon 5600 Series QuickPath Architecture Generic Non-core Registers (rev 02) ff:00.1 Host bridge: Intel Corporation Xeon 5600 Series QuickPath Architecture System Address Decoder (rev 02) ff:02.0 Host bridge: Intel Corporation Xeon 5600 Series QPI Link 0 (rev 02) ff:02.1 Host bridge: Intel Corporation Xeon 5600 Series QPI Physical 0 (rev 02) ff:02.2 Host bridge: Intel Corporation Xeon 5600 Series Mirror Port Link 0 (rev 02) ff:02.3 Host bridge: Intel Corporation Xeon 5600 Series Mirror Port Link 1 (rev 02) ff:02.4 Host bridge: Intel Corporation Xeon 5600 Series QPI Link 1 (rev 02) ff:02.5 Host bridge: Intel Corporation Xeon 5600 Series QPI Physical 1 (rev 02) ff:03.0 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Registers (rev 02) ff:03.1 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Target Address Decoder (rev 02) ff:03.2 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller RAS Registers (rev 02) ff:03.4 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Test Registers (rev 02) ff:04.0 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 0 Control (rev 02) ff:04.1 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 0 Address (rev 02) ff:04.2 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 0 Rank (rev 02) ff:04.3 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 0 Thermal Control (rev 02) ff:05.0 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 1 Control (rev 02) ff:05.1 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 1 Address (rev 02) ff:05.2 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 1 Rank (rev 02) ff:05.3 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 1 Thermal Control (rev 02) ff:06.0 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 2 Control (rev 02) ff:06.1 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 2 Address (rev 02) ff:06.2 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 2 Rank (rev 02) ff:06.3 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 2 Thermal Control (rev 02) Do you use a similar hardware? Cheers, David -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
