Driver ip.docker
Minimal configlet:
[ip#1]
type = docker
Minimal setup command:
om test/vol/foo set --kw="type=docker"
Supported keywords:
- comment
- pg_blkio_weight
- pg_cpu_burst
- pg_cpu_quota
- pg_cpu_shares
- pg_cpus
- pg_mem_high
- pg_mem_limit
- pg_mem_oom_control
- pg_mem_swappiness
- pg_mems
- pg_pids_max
- pg_vmem_limit
- stat_timeout
- type
Keyword comment
required: false
scopable: false
Description:
A free form text describing the role of the object, of the node, or of the section it is set in.
The keyword is accepted in any section, so the DEFAULT section can document a configuration as a whole, and a resource, pool, heartbeat, array or network section can document itself.
The agent does not interpret the value.
Keyword pg_blkio_weight
required: false
scopable: true
Example:
pg_blkio_weight=50
Description:
Block IO relative weight. Value: between 10 and 1000.
The kernel default is 100.
Setting this keyword to default puts the capping back where a node that
never capped anything leaves it. Removing the keyword does not: what was
written stays written, whether om wrote it or something else did.
Keyword pg_cpu_burst
required: false
scopable: true
Example:
pg_cpu_burst=20%
Description:
The cpu time the group banks under its quota, and spends above it.
It is the time the processes of the group may bank while under their
pg_cpu_quota, and spend above it in a short spike, in the notation of
pg_cpu_quota: 20% lets the group run a fifth of a cpu above its quota
during a period, out of what it left unused before.
It serves a latency-sensitive service capped tightly: a request arriving after an idle spell is served at the speed of the burst, rather than throttled for the rest of the period. Over a longer time the group still uses no more than its quota.
It needs pg_cpu_quota, and cannot exceed it: the kernel refuses a burst
larger than the quota. Only the unified cgroup hierarchy has it.
Setting this keyword to default puts the capping back where a node that
never capped anything leaves it. Removing the keyword does not: what was
written stays written, whether om wrote it or something else did.
Keyword pg_cpu_quota
required: false
scopable: true
Example:
pg_cpu_quota=50%@all
Description:
The percentage of cpu time the processes of the group may use.
Accepted expressions:
-
50%Half of one cpu. -
50%@allHalf of every cpu the node has. -
10%@2A tenth of two cpus.
Unlike pg_cpu_shares, which only arbitrates when the node is cpu-bound, a
quota caps the group whether or not the node is busy.
Setting this keyword to default puts the capping back where a node that
never capped anything leaves it. Removing the keyword does not: what was
written stays written, whether om wrote it or something else did.
Keyword pg_cpu_shares
required: false
scopable: true
convert: size
Example:
pg_cpu_shares=512
Description:
The share of cpu the group gets when the node is cpu-bound.
The share is relative to the other groups.
The actual percentile depends on the shares allowed to the other services. Unset, the kernel default is used, which usually is 1024 shares.
Setting this keyword to default puts the capping back where a node that
never capped anything leaves it. Removing the keyword does not: what was
written stays written, whether om wrote it or something else did.
Keyword pg_cpus
required: false
scopable: true
depends: create_pg=true
Example:
pg_cpus=0-2
Description:
The cpus the processes of the group may run on.
Cpus are specified as list or range : 0,1,2 or 0-2.
Setting this keyword to default puts the capping back where a node that
never capped anything leaves it. Removing the keyword does not: what was
written stays written, whether om wrote it or something else did.
Keyword pg_mem_high
required: false
scopable: true
convert: size
Example:
pg_mem_high=384m
Description:
The memory past which the kernel throttles the group, in bytes.
Past it, the kernel slows the processes of the group down, reclaiming their memory and throttling their allocations.
Unlike pg_mem_limit, reaching it does not wake the Out-Of-Memory killer: a
group above it keeps running, slower, while the kernel reclaims. Set below
pg_mem_limit, it gives a process growing too much the time to be noticed,
or to shrink, before it is killed.
It is a soft limit, so it is not what a memory claim counts: the claim counts
pg_mem_limit. Only the unified cgroup hierarchy has it.
Setting this keyword to default puts the capping back where a node that
never capped anything leaves it. Removing the keyword does not: what was
written stays written, whether om wrote it or something else did.
Keyword pg_mem_limit
required: false
scopable: true
convert: size
Example:
pg_mem_limit=512m
Description:
The memory the processes of the group may use, in bytes.
The Out-Of-Memory killer is triggered in case of tresspassing.
Setting this keyword to default puts the capping back where a node that
never capped anything leaves it. Removing the keyword does not: what was
written stays written, whether om wrote it or something else did.
Keyword pg_mem_oom_control
required: false
scopable: true
Example:
pg_mem_oom_control=1
Description:
Whether the Out of Memory killer runs for the group: 0 enables it.
It is a flag (0 or 1) enabling or disabling the Out of Memory killer for the processes of the group.
- If enabled (0), tasks that attempt to consume more memory than they are allowed are immediately killed by the OOM killer.
- If disabled (1), tasks are allowed to continue to try allocating memory, stressing the system.
The OOM killer is enabled by default in every cgroup using the memory controller.
This keyword caps nothing on a node holding the unified cgroup hierarchy,
which has no memory.oom_control: that file is of the v1 hierarchy. Setting
it there is warned about, and ignored.
Keyword pg_mem_swappiness
required: false
scopable: true
Example:
pg_mem_swappiness=40
Description:
Set a swappiness percentile value for the process group.
This keyword caps nothing on a node holding the unified cgroup hierarchy,
which has no memory.swappiness: that file is of the v1 hierarchy. Setting
it there is warned about, and ignored.
Keyword pg_mems
required: false
scopable: true
Example:
pg_mems=0-2
Description:
The memory nodes the processes of the group may allocate from.
Memory nodes are specified as list or range : 0,1,2 or 0-2.
Setting this keyword to default puts the capping back where a node that
never capped anything leaves it. Removing the keyword does not: what was
written stays written, whether om wrote it or something else did.
Keyword pg_pids_max
required: false
scopable: true
Example:
pg_pids_max=512
Description:
The most processes and threads the group may run at once.
A fork beyond it fails in the process that asked for it, and nothing else of the node is touched: it is what keeps a runaway fork loop from exhausting the process table of the node.
Setting this keyword to default puts the capping back where a node that
never capped anything leaves it. Removing the keyword does not: what was
written stays written, whether om wrote it or something else did.
Keyword pg_vmem_limit
required: false
scopable: true
convert: size
Example:
pg_vmem_limit=1g
Description:
The memory plus swap the processes of the group may use, in bytes.
The Out-Of-Memory killer is triggered in case of tresspassing.
The specified value must be greater than pg_mem_limit.
Setting this keyword to default puts the capping back where a node that
never capped anything leaves it. Removing the keyword does not: what was
written stays written, whether om wrote it or something else did.
Keyword stat_timeout
required: false
scopable: true
convert: duration
Description:
The fs resources status evaluation includes a stat syscall test. This keyword defines the maximum wait time for those stat calls to respond.
When expired, the resource status is degraded is to warn, which can trigger a monitor action (reboot or crash the node) if the resource is monitored.
Keyword type
required: false
scopable: false
rbac: Requires the root grant, except for a cni address, and for a netns address om draws from a cluster network.
Description:
The resource driver name.