MBA Software Controller feature is introduced in Linux kernel v4.18.
It is a software enhancement to mitigate some limitations in MBA which
describes in kernel documentation. It also makes the interface more user
friendly - we could specify memory bandwidth in "MBps" (Mega Bytes per
second) as well as in "percentages".
The kernel underneath would use a software feedback mechanism or a
"Software Controller" which reads the actual bandwidth using MBM
counters and adjust the memory bandwidth percentages to ensure:
"actual memory bandwidth < user specified memory bandwidth".
We could enable this feature through mount option "-o mba_MBps":
mount -t resctrl resctrl -o mba_MBps /sys/fs/resctrl
In runc, we handle both memory bandwidth schemata in unified format:
"MB:<cache_id0>=bandwidth0;<cache_id1>=bandwidth1;..."
The unit of memory bandwidth is specified in "percentages" by default,
and in "MBps" if MBA Software Controller is enabled.
For more information about Intel RDT and MBA Software Controller:
https://www.kernel.org/doc/Documentation/x86/intel_rdt_ui.txt
Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com>
Cgroup namespace can be configured in `config.json` as other
namespaces. Here is an example:
```
"namespaces": [
{
"type": "pid"
},
{
"type": "network"
},
{
"type": "ipc"
},
{
"type": "uts"
},
{
"type": "mount"
},
{
"type": "cgroup"
}
],
```
Note that if you want to run a container which has shared cgroup ns with
another container, then it's strongly recommended that you set
proper `CgroupsPath` of both containers(the second container's cgroup
path must be the subdirectory of the first one). Or there might be
some unexpected results.
Signed-off-by: Yuanhong Peng <pengyuanhong@huawei.com>
Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
This device is not required by the OCI spec.
The rationale for this was linked to https://github.com/docker/docker/issues/2393
So a non functional /dev/fuse was created, and actual fuse use still is
required to add the device explicitly. However even old versions of the JVM
on Ubuntu 12.04 no longer require the fuse package, and this is all not
needed.
Signed-off-by: Justin Cormack <justin.cormack@docker.com>
The spec uses symlinks to "/proc/1/..." but the implementation uses
"/proc/self/...": see setupDevSymlinks (libcontainer/rootfs_linux.go).
The implementation is more correct, so I'm changing the spec to match
the implementation.
Signed-off-by: Alban Crequy <alban.crequy@coreos.com>