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Diffstat (limited to 'Documentation/cpusets.txt')
| -rw-r--r-- | Documentation/cpusets.txt | 26 |
1 files changed, 14 insertions, 12 deletions
diff --git a/Documentation/cpusets.txt b/Documentation/cpusets.txt index aa854b9b18c..fb7b361e6ee 100644 --- a/Documentation/cpusets.txt +++ b/Documentation/cpusets.txt @@ -171,6 +171,7 @@ files describing that cpuset: - memory_migrate flag: if set, move pages to cpusets nodes - cpu_exclusive flag: is cpu placement exclusive? - mem_exclusive flag: is memory placement exclusive? + - mem_hardwall flag: is memory allocation hardwalled - memory_pressure: measure of how much paging pressure in cpuset In addition, the root cpuset only has the following file: @@ -222,17 +223,18 @@ If a cpuset is cpu or mem exclusive, no other cpuset, other than a direct ancestor or descendent, may share any of the same CPUs or Memory Nodes. -A cpuset that is mem_exclusive restricts kernel allocations for -page, buffer and other data commonly shared by the kernel across -multiple users. All cpusets, whether mem_exclusive or not, restrict -allocations of memory for user space. This enables configuring a -system so that several independent jobs can share common kernel data, -such as file system pages, while isolating each jobs user allocation in -its own cpuset. To do this, construct a large mem_exclusive cpuset to -hold all the jobs, and construct child, non-mem_exclusive cpusets for -each individual job. Only a small amount of typical kernel memory, -such as requests from interrupt handlers, is allowed to be taken -outside even a mem_exclusive cpuset. +A cpuset that is mem_exclusive *or* mem_hardwall is "hardwalled", +i.e. it restricts kernel allocations for page, buffer and other data +commonly shared by the kernel across multiple users. All cpusets, +whether hardwalled or not, restrict allocations of memory for user +space. This enables configuring a system so that several independent +jobs can share common kernel data, such as file system pages, while +isolating each job's user allocation in its own cpuset. To do this, +construct a large mem_exclusive cpuset to hold all the jobs, and +construct child, non-mem_exclusive cpusets for each individual job. +Only a small amount of typical kernel memory, such as requests from +interrupt handlers, is allowed to be taken outside even a +mem_exclusive cpuset. 1.5 What is memory_pressure ? @@ -707,7 +709,7 @@ Now you want to do something with this cpuset. In this directory you can find several files: # ls -cpus cpu_exclusive mems mem_exclusive tasks +cpus cpu_exclusive mems mem_exclusive mem_hardwall tasks Reading them will give you information about the state of this cpuset: the CPUs and Memory Nodes it can use, the processes that are using |