Devin--what is the output of the command "dmesg"
Are there any kernel traces or bugs in that output?
Steve
On Wed, 8 Sep 2010, Devin Bougie wrote:
> Hi, All. We are seeing periodic I/O delays on a new large compute node using two Xeon X5670 CPU's (hyper-threaded for a total of 24 processors) with 48GB memory. The system is running the latest kernel on a fully updated x86_64 SL5.5. So far my attempts at changing schedulers and BIOS configurations has not helped. This is a unique system for us, and I have not been able to reproduce this on any other x86_64 SL5.5 systems. Various benchmarks we've run (most extensively using Mathematica) show the system performing very well. So far we've only seen the problem when performing disk I/O.
>
> Please let me know if there is any more information I can provide, and any suggestions would be greatly appreciated.
>
> Many thanks,
> Devin
>
> ------
>
> Here is an example of how we can reproduce the delays by repeatedly writing modest amounts of data.
>
> ------
> [dab66@lnx4103 ~]% time dd if=/dev/zero of=/mnt/scratch/test bs=1M count=1K
> 1024+0 records in
> 1024+0 records out
> 1073741824 bytes (1.1 GB) copied, 0.914825 seconds, 1.2 GB/s
>
> real 0m2.037s
> user 0m0.000s
> sys 0m1.050s
> [dab66@lnx4103 ~]% time dd if=/dev/zero of=/mnt/scratch/test bs=1M count=1K
> 1024+0 records in
> 1024+0 records out
> 1073741824 bytes (1.1 GB) copied, 0.903858 seconds, 1.2 GB/s
>
> real 0m1.129s
> user 0m0.001s
> sys 0m1.125s
> [dab66@lnx4103 ~]% time dd if=/dev/zero of=/mnt/scratch/test bs=1M count=1K
> 1024+0 records in
> 1024+0 records out
> 1073741824 bytes (1.1 GB) copied, 0.923554 seconds, 1.2 GB/s
>
> real 0m1.141s
> user 0m0.001s
> sys 0m1.138s
> [dab66@lnx4103 ~]% time dd if=/dev/zero of=/mnt/scratch/test bs=1M count=1K
> 1024+0 records in
> 1024+0 records out
> 1073741824 bytes (1.1 GB) copied, 0.911595 seconds, 1.2 GB/s
>
> real 1m27.200s
> user 0m0.001s
> sys 0m1.148s
>
> ------
>
> Here is a look at "vmstat -S M 5" before, during, and after the above tests.
>
> ------
> procs -----------memory---------- ---swap-- -----io---- --system-- -----cpu------
> r b swpd free buff cache si so bi bo in cs us sy id wa st
> 0 0 0 46937 35 1184 0 0 4 81 43 7 0 0 98 2 0
> 0 0 0 46937 35 1184 0 0 1 18 1017 85 0 0 100 0 0
> 0 0 0 46937 35 1184 0 0 0 5 1013 93 0 0 100 0 0
> 0 0 0 46937 35 1184 0 0 0 42 1017 84 0 0 100 0 0
> 0 1 0 46937 35 1184 0 0 1 2 1005 91 0 0 100 0 0
> 0 0 0 46937 35 1184 0 0 0 17 1016 90 0 0 100 0 0
> 0 0 0 46937 35 1184 0 0 0 5 1012 89 0 0 100 0 0
> 0 0 0 46937 35 1184 0 0 0 5 1010 85 0 0 100 0 0
> 0 1 0 46919 35 1186 0 0 596 12 1071 224 0 0 99 1 0
> 0 0 0 46919 35 1186 0 0 0 70 1019 89 0 0 100 0 0
> 0 0 0 46919 35 1186 0 0 0 11 1015 98 0 0 100 0 0
> 0 0 0 46919 35 1186 0 0 0 7 1021 112 0 0 100 0 0
> 1 0 0 47780 38 337 0 0 0 31 1035 760 0 2 98 0 0
> 0 5 0 46929 38 1135 0 0 0 26431 1040 341 0 1 94 5 0
> 0 6 0 46986 38 1081 0 0 2 9840 1032 158 0 0 84 16 0
> 0 6 0 47054 39 1013 0 0 65 13113 1052 186 0 0 85 15 0
> 0 5 0 47137 39 948 0 0 2 13006 1036 171 0 0 86 14 0
> 0 7 0 47208 39 881 0 0 0 13135 1035 161 0 0 86 14 0
> 0 6 0 47258 39 833 0 0 0 9736 1031 150 0 0 84 16 0
> 0 6 0 47300 39 793 0 0 0 8656 1025 131 0 0 83 17 0
> 0 5 0 47349 39 750 0 0 0 2 1027 569 0 0 89 11 0
> procs -----------memory---------- ---swap-- -----io---- --system-- -----cpu------
> r b swpd free buff cache si so bi bo in cs us sy id wa st
> 0 3 0 47437 39 660 0 0 0 26781 1042 1372 0 0 88 12 0
> 0 5 0 47517 39 585 0 0 0 13008 1041 177 0 0 85 15 0
> 0 5 0 47571 39 531 0 0 0 13107 1030 148 0 0 83 17 0
> 0 5 0 47622 39 484 0 0 0 9734 1033 150 0 0 87 13 0
> 0 5 0 47668 39 440 0 0 0 6554 1029 134 0 0 87 12 0
> 0 5 0 47711 39 399 0 0 1 9832 1027 146 0 0 83 17 0
> 0 4 0 47772 39 340 0 0 0 13006 1036 149 0 0 85 15 0
> 0 5 0 47841 39 275 0 0 0 13110 1037 164 0 0 86 14 0
> 0 5 0 47909 39 212 0 0 0 6754 1037 310 0 0 87 13 0
> 0 1 0 46894 39 1186 0 0 0 11842 1031 1825 0 1 93 6 0
> 0 4 0 46892 39 1186 0 0 0 27131 1055 104 0 0 95 5 0
> 0 4 0 46893 39 1186 0 0 0 9834 1025 110 0 0 93 6 0
> 0 5 0 46893 39 1186 0 0 0 6557 1031 105 0 0 91 9 0
> 0 5 0 46893 39 1186 0 0 0 9732 1022 114 0 0 93 7 0
> 0 5 0 46894 39 1186 0 0 0 6554 1021 104 0 0 96 4 0
> 0 5 0 46893 39 1186 0 0 0 9837 1035 120 0 0 91 9 0
> 0 4 0 46893 39 1186 0 0 0 13010 1039 103 0 0 96 4 0
> 0 4 0 46893 39 1186 0 0 0 16283 1043 115 0 0 92 8 0
> 0 4 0 46894 39 1186 0 0 0 9832 1033 103 0 0 92 8 0
> ------
>
> And attached is a look at "iostat -m -x 5".
>
> Here is some basic system information.
>
> ------
> [root@lnx4103 ~]# cat /proc/cpuinfo
> processor : 0
> vendor_id : GenuineIntel
> cpu family : 6
> model : 44
> model name : Intel(R) Xeon(R) CPU X5670 @ 2.93GHz
> stepping : 2
> cpu MHz : 2933.540
> cache size : 12288 KB
> physical id : 0
> siblings : 12
> core id : 0
> cpu cores : 6
> apicid : 0
> fpu : yes
> fpu_exception : yes
> cpuid level : 11
> 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 syscall nx pdpe1gb rdtscp lm constant_tsc nonstop_tsc arat pni monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr sse4_1 sse4_2 popcnt lahf_lm
> bogomips : 5867.08
> clflush size : 64
> cache_alignment : 64
> address sizes : 40 bits physical, 48 bits virtual
> power management: [8]
>
> processor : 1
> vendor_id : GenuineIntel
> cpu family : 6
> model : 44
> model name : Intel(R) Xeon(R) CPU X5670 @ 2.93GHz
> stepping : 2
> cpu MHz : 2933.540
> cache size : 12288 KB
> physical id : 0
> siblings : 12
> core id : 1
> cpu cores : 6
> apicid : 2
> fpu : yes
> fpu_exception : yes
> cpuid level : 11
> 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 syscall nx pdpe1gb rdtscp lm constant_tsc nonstop_tsc arat pni monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr sse4_1 sse4_2 popcnt lahf_lm
> bogomips : 5866.57
> clflush size : 64
> cache_alignment : 64
> address sizes : 40 bits physical, 48 bits virtual
> power management: [8]
>
> ...
>
> processor : 22
> vendor_id : GenuineIntel
> cpu family : 6
> model : 44
> model name : Intel(R) Xeon(R) CPU X5670 @ 2.93GHz
> stepping : 2
> cpu MHz : 2933.540
> cache size : 12288 KB
> physical id : 1
> siblings : 12
> core id : 9
> cpu cores : 6
> apicid : 51
> fpu : yes
> fpu_exception : yes
> cpuid level : 11
> 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 syscall nx pdpe1gb rdtscp lm constant_tsc nonstop_tsc arat pni monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr sse4_1 sse4_2 popcnt lahf_lm
> bogomips : 5866.79
> clflush size : 64
> cache_alignment : 64
> address sizes : 40 bits physical, 48 bits virtual
> power management: [8]
>
> processor : 23
> vendor_id : GenuineIntel
> cpu family : 6
> model : 44
> model name : Intel(R) Xeon(R) CPU X5670 @ 2.93GHz
> stepping : 2
> cpu MHz : 2933.540
> cache size : 12288 KB
> physical id : 1
> siblings : 12
> core id : 10
> cpu cores : 6
> apicid : 53
> fpu : yes
> fpu_exception : yes
> cpuid level : 11
> 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 syscall nx pdpe1gb rdtscp lm constant_tsc nonstop_tsc arat pni monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr sse4_1 sse4_2 popcnt lahf_lm
> bogomips : 5866.95
> clflush size : 64
> cache_alignment : 64
> address sizes : 40 bits physical, 48 bits virtual
> power management: [8]
> ------
>
> [root@lnx4103 ~]# lspci
> 00:00.0 Host bridge: Intel Corporation 5500 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)
> 00:02.0 PCI bridge: Intel Corporation 5520/5500/X58 I/O Hub PCI Express Root Port 2 (rev 22)
> 00:03.0 PCI bridge: Intel Corporation 5520/5500/X58 I/O Hub PCI Express Root Port 3 (rev 22)
> 00:07.0 PCI bridge: Intel Corporation 5520/5500/X58 I/O Hub PCI Express Root Port 7 (rev 22)
> 00:08.0 PCI bridge: Intel Corporation 5520/5500/X58 I/O Hub PCI Express Root Port 8 (rev 22)
> 00:09.0 PCI bridge: Intel Corporation 5520/5500/X58 I/O Hub PCI Express Root Port 9 (rev 22)
> 00:0a.0 PCI bridge: Intel Corporation 5520/5500/X58 I/O Hub PCI Express Root Port 10 (rev 22)
> 00:10.0 PIC: Intel Corporation 5520/5500/X58 Physical and Link Layer Registers Port 0 (rev 22)
> 00:10.1 PIC: Intel Corporation 5520/5500/X58 Routing and Protocol Layer Registers Port 0 (rev 22)
> 00:11.0 PIC: Intel Corporation 5520/5500 Physical and Link Layer Registers Port 1 (rev 22)
> 00:11.1 PIC: Intel Corporation 5520/5500 Routing & Protocol Layer Register Port 1 (rev 22)
> 00:14.0 PIC: Intel Corporation 5520/5500/X58 I/O Hub System Management Registers (rev 22)
> 00:14.1 PIC: Intel Corporation 5520/5500/X58 I/O Hub GPIO and Scratch Pad Registers (rev 22)
> 00:14.2 PIC: Intel Corporation 5520/5500/X58 I/O Hub Control Status and RAS Registers (rev 22)
> 00:14.3 PIC: Intel Corporation 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.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.3 USB Controller: Intel Corporation 82801JI (ICH10 Family) USB UHCI Controller #6
> 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 IDE interface: Intel Corporation 82801JI (ICH10 Family) 4 port SATA IDE Controller #1
> 00:1f.3 SMBus: Intel Corporation 82801JI (ICH10 Family) SMBus Controller
> 00:1f.5 IDE interface: Intel Corporation 82801JI (ICH10 Family) 2 port SATA IDE Controller #2
> 01:01.0 VGA compatible controller: ASPEED Technology, Inc. ASPEED Graphics Family (rev 10)
> 02:00.0 Ethernet controller: Intel Corporation 82574L Gigabit Network Connection
> 03:00.0 Ethernet controller: Intel Corporation 82574L Gigabit Network Connection
> ------
>
>
--
------------------------------------------------------------------
Steven C. Timm, Ph.D (630) 840-8525
[log in to unmask] http://home.fnal.gov/~timm/
Fermilab Computing Division, Scientific Computing Facilities,
Grid Facilities Department, FermiGrid Services Group, Assistant Group Leader.
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