diff options
author | Jiri Kosina <jkosina@suse.cz> | 2011-04-26 10:22:15 +0200 |
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committer | Jiri Kosina <jkosina@suse.cz> | 2011-04-26 10:22:59 +0200 |
commit | 07f9479a40cc778bc1462ada11f95b01360ae4ff (patch) | |
tree | 0676cf38df3844004bb3ebfd99dfa67a4a8998f5 /Documentation/cgroups | |
parent | 9d5e6bdb3013acfb311ab407eeca0b6a6a3dedbf (diff) | |
parent | cd2e49e90f1cae7726c9a2c54488d881d7f1cd1c (diff) |
Merge branch 'master' into for-next
Fast-forwarded to current state of Linus' tree as there are patches to be
applied for files that didn't exist on the old branch.
Diffstat (limited to 'Documentation/cgroups')
-rw-r--r-- | Documentation/cgroups/blkio-controller.txt | 30 | ||||
-rw-r--r-- | Documentation/cgroups/cgroups.txt | 12 |
2 files changed, 7 insertions, 35 deletions
diff --git a/Documentation/cgroups/blkio-controller.txt b/Documentation/cgroups/blkio-controller.txt index 4ed7b5ceeed..465351d4cf8 100644 --- a/Documentation/cgroups/blkio-controller.txt +++ b/Documentation/cgroups/blkio-controller.txt @@ -140,7 +140,7 @@ Proportional weight policy files - Specifies per cgroup weight. This is default weight of the group on all the devices until and unless overridden by per device rule. (See blkio.weight_device). - Currently allowed range of weights is from 100 to 1000. + Currently allowed range of weights is from 10 to 1000. - blkio.weight_device - One can specify per cgroup per device rules using this interface. @@ -343,34 +343,6 @@ Common files among various policies CFQ sysfs tunable ================= -/sys/block/<disk>/queue/iosched/group_isolation ------------------------------------------------ - -If group_isolation=1, it provides stronger isolation between groups at the -expense of throughput. By default group_isolation is 0. In general that -means that if group_isolation=0, expect fairness for sequential workload -only. Set group_isolation=1 to see fairness for random IO workload also. - -Generally CFQ will put random seeky workload in sync-noidle category. CFQ -will disable idling on these queues and it does a collective idling on group -of such queues. Generally these are slow moving queues and if there is a -sync-noidle service tree in each group, that group gets exclusive access to -disk for certain period. That means it will bring the throughput down if -group does not have enough IO to drive deeper queue depths and utilize disk -capacity to the fullest in the slice allocated to it. But the flip side is -that even a random reader should get better latencies and overall throughput -if there are lots of sequential readers/sync-idle workload running in the -system. - -If group_isolation=0, then CFQ automatically moves all the random seeky queues -in the root group. That means there will be no service differentiation for -that kind of workload. This leads to better throughput as we do collective -idling on root sync-noidle tree. - -By default one should run with group_isolation=0. If that is not sufficient -and one wants stronger isolation between groups, then set group_isolation=1 -but this will come at cost of reduced throughput. - /sys/block/<disk>/queue/iosched/slice_idle ------------------------------------------ On a faster hardware CFQ can be slow, especially with sequential workload. diff --git a/Documentation/cgroups/cgroups.txt b/Documentation/cgroups/cgroups.txt index cbdfb7d9455..aedf1bd02fd 100644 --- a/Documentation/cgroups/cgroups.txt +++ b/Documentation/cgroups/cgroups.txt @@ -110,22 +110,22 @@ university server with various users - students, professors, system tasks etc. The resource planning for this server could be along the following lines: - CPU : Top cpuset + CPU : "Top cpuset" / \ CPUSet1 CPUSet2 - | | - (Profs) (Students) + | | + (Professors) (Students) In addition (system tasks) are attached to topcpuset (so that they can run anywhere) with a limit of 20% - Memory : Professors (50%), students (30%), system (20%) + Memory : Professors (50%), Students (30%), system (20%) - Disk : Prof (50%), students (30%), system (20%) + Disk : Professors (50%), Students (30%), system (20%) Network : WWW browsing (20%), Network File System (60%), others (20%) / \ - Prof (15%) students (5%) + Professors (15%) students (5%) Browsers like Firefox/Lynx go into the WWW network class, while (k)nfsd go into NFS network class. |