Automatic merge from submit-queue
kubelet/cadvisor: Refactor cadvisor disk stat/usage interfaces.
basically
1) cadvisor struct will know what runtime the kubelet is, passed in via additional argument to New()
2) rename cadvisor wrapper function to DockerImagesFsInfo() to ImagesFsInfo() and have linux implementation choose a label based on the runtime inside the cadvisor struct
2a) mock/fake/unsupported modified to take the same additional argument in New()
3) kubelet's wrapper for the cadvisor wrapper is renamed in parallel
4) make all tests use new interface
Automatic merge from submit-queue
Expose SummaryProvider for reuse by other parts of kubelet
To support out of resource killing in the kubelet, we will introduce a new top-level module that will ensure node stability by checking if eviction thresholds have been met for memory and file-system usage on the node. In addition, it will then need information about pod memory and disk usage in order to make an eviction selection. Currently, this information is collected in `SummaryProvider` but it's hidden away and not available for re-use by other top-level modules of the kubelet. This initial refactor adds the ability to get summary stat information from the `ResourceAnalyzer` so it can be reused by other top-level modules.
I suspect we will further re-factor this area as code evolves, but this unblocks further progress on out-of-resource killing.
/cc @vishh @timothysc @kubernetes/sig-node @kubernetes/rh-cluster-infra
Automatic merge from submit-queue
Add memory available to summary stats provider
To support out of resource killing when low on memory, we want to let operators specify eviction thresholds based on available memory instead of memory usage for ease of use when working with heterogeneous nodes.
So for example, a valid eviction threshold would be the following:
* If node.memory.available < 200Mi for 30s, then evict pod(s)
For the node, `memory.availableBytes` is always known since the `memory.limit_in_bytes` is always known for root cgroup. For individual containers in pods, we only populate the `availableBytes` if the container was launched with a memory limit specified. When no memory limit is specified, the cgroupfs sets a value of 1 << 63 in the `memory.limit_in_bytes` so we look for a similar max value to handle unbounded limits, and ignore setting `memory.availableBytes`.
FYI @vishh @timstclair - as discussed on Slack.
/cc @kubernetes/sig-node @kubernetes/rh-cluster-infra
Automatic merge from submit-queue
Refactor streaming code to support interop testing
Refactor exec/attach/port forward client and server code to better
support interop testing of different client and server subprotocol
versions.
Fixes#16119
PLEG is reponsible for listing the pods running on the node. If it's hung
due to non-responsive container runtime or internal bugs, we should restart
kubelet.
`--kubelet-cgroups` and `--system-cgroups` respectively.
Updated `--runtime-container` to `--runtime-cgroups`.
Cleaned up most of the kubelet code that consumes these flags to match
the flag name changes.
Signed-off-by: Vishnu kannan <vishnuk@google.com>
* Metrics will not be expose until they are hooked up to a handler
* Metrics are not cached and expose a dos vector, this must be fixed before release or the stats should not be exposed through an api endpoint
Many users attempt to use 'kubectl logs' in order to find the logs
for a container, but receive no logs or an error telling them their
container is not running. The fix in this case is to run with '--previous',
but this does not match user expectations for the logs command.
This commit changes the behavior of the Kubelet to return the logs of
the currently running container or the previous running container unless
the user provides the "previous" flag. If the user specifies "follow"
the logs of the most recent container will be displayed, and if it is
a terminated container the logs will come to an end (the user can
repeatedly invoke 'kubectl logs --follow' and see the same output).
Clean up error messages in the kubelet log path to be consistent and
give users a more predictable experience.
Have the Kubelet return 400 on invalid requests
Add a `/stats/summary` endpoint to the kubelet which will return an
empty Summary{} struct (json formatted), as a summary API
placeholder. Once the next cAdvisor release is vendored, the summary
API will be filled in.
Changes include:
- Moving stats serving & routes to pkg/kubelet/server/stats/handler.go
- Managing the routes with restful.WebService, rather than manual
parsing
- Misc cleanup
These changes will make adding the new routes for /stats/summary more
manageable.
