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Diffstat (limited to 'Documentation/powerpc/vcpudispatch_stats.txt')
| -rw-r--r-- | Documentation/powerpc/vcpudispatch_stats.txt | 68 |
1 files changed, 0 insertions, 68 deletions
diff --git a/Documentation/powerpc/vcpudispatch_stats.txt b/Documentation/powerpc/vcpudispatch_stats.txt deleted file mode 100644 index e21476bfd78c..000000000000 --- a/Documentation/powerpc/vcpudispatch_stats.txt +++ /dev/null @@ -1,68 +0,0 @@ -VCPU Dispatch Statistics: -========================= - -For Shared Processor LPARs, the POWER Hypervisor maintains a relatively -static mapping of the LPAR processors (vcpus) to physical processor -chips (representing the "home" node) and tries to always dispatch vcpus -on their associated physical processor chip. However, under certain -scenarios, vcpus may be dispatched on a different processor chip (away -from its home node). - -/proc/powerpc/vcpudispatch_stats can be used to obtain statistics -related to the vcpu dispatch behavior. Writing '1' to this file enables -collecting the statistics, while writing '0' disables the statistics. -By default, the DTLB log for each vcpu is processed 50 times a second so -as not to miss any entries. This processing frequency can be changed -through /proc/powerpc/vcpudispatch_stats_freq. - -The statistics themselves are available by reading the procfs file -/proc/powerpc/vcpudispatch_stats. Each line in the output corresponds to -a vcpu as represented by the first field, followed by 8 numbers. - -The first number corresponds to: -1. total vcpu dispatches since the beginning of statistics collection - -The next 4 numbers represent vcpu dispatch dispersions: -2. number of times this vcpu was dispatched on the same processor as last - time -3. number of times this vcpu was dispatched on a different processor core - as last time, but within the same chip -4. number of times this vcpu was dispatched on a different chip -5. number of times this vcpu was dispatches on a different socket/drawer -(next numa boundary) - -The final 3 numbers represent statistics in relation to the home node of -the vcpu: -6. number of times this vcpu was dispatched in its home node (chip) -7. number of times this vcpu was dispatched in a different node -8. number of times this vcpu was dispatched in a node further away (numa -distance) - -An example output: - $ sudo cat /proc/powerpc/vcpudispatch_stats - cpu0 6839 4126 2683 30 0 6821 18 0 - cpu1 2515 1274 1229 12 0 2509 6 0 - cpu2 2317 1198 1109 10 0 2312 5 0 - cpu3 2259 1165 1088 6 0 2256 3 0 - cpu4 2205 1143 1056 6 0 2202 3 0 - cpu5 2165 1121 1038 6 0 2162 3 0 - cpu6 2183 1127 1050 6 0 2180 3 0 - cpu7 2193 1133 1052 8 0 2187 6 0 - cpu8 2165 1115 1032 18 0 2156 9 0 - cpu9 2301 1252 1033 16 0 2293 8 0 - cpu10 2197 1138 1041 18 0 2187 10 0 - cpu11 2273 1185 1062 26 0 2260 13 0 - cpu12 2186 1125 1043 18 0 2177 9 0 - cpu13 2161 1115 1030 16 0 2153 8 0 - cpu14 2206 1153 1033 20 0 2196 10 0 - cpu15 2163 1115 1032 16 0 2155 8 0 - -In the output above, for vcpu0, there have been 6839 dispatches since -statistics were enabled. 4126 of those dispatches were on the same -physical cpu as the last time. 2683 were on a different core, but within -the same chip, while 30 dispatches were on a different chip compared to -its last dispatch. - -Also, out of the total of 6839 dispatches, we see that there have been -6821 dispatches on the vcpu's home node, while 18 dispatches were -outside its home node, on a neighbouring chip. |