cpu.cfs_period_us is 100μs by default despite having an "ms" unit
for some unfortunate reason. Documentation:
https://www.kernel.org/doc/html/latest/scheduler/sched-bwc.html#management
The desired effect of that change is more clarity on the default value
so users would be aware that the 10ms custom value would be
not 0.1x of the default, but 100x of it.
It is useful to have the ability to control whether alpha or beta features are
enabled. We can group features under LoggingAlphaOptions and LoggingBetaOptions
because the configuration is designed so that each feature individually must be
enabled via its own option.
Currently, the JSON format itself is beta (graduated in 1.23) but additional
options for it were only added in 1.23 and thus are still alpha:
$ go run ./staging/src/k8s.io/component-base/logs/example/cmd/logger.go --logging-format=json --log-json-split-stream --log-json-info-buffer-size 1M --feature-gates LoggingBetaOptions=false
[format: Forbidden: Log format json is BETA and disabled, see LoggingBetaOptions feature, options.json.splitStream: Forbidden: Feature LoggingAlphaOptions is disabled, options.json.infoBufferSize: Forbidden: Feature LoggingAlphaOptions is disabled]
$ go run ./staging/src/k8s.io/component-base/logs/example/cmd/logger.go --logging-format=json --log-json-split-stream --log-json-info-buffer-size 1M
[options.json.splitStream: Forbidden: Feature LoggingAlphaOptions is disabled, options.json.infoBufferSize: Forbidden: Feature LoggingAlphaOptions is disabled]
This is the same approach that was taken for CPUManagerPolicyAlphaOptions and
CPUManagerPolicyBetaOptions.
In order to test this without modifying the global feature gate in a test file,
ValidateKubeletConfiguration must take a feature gate as argument.
Making the LoggingConfiguration part of the versioned component-base/config API
had the theoretic advantage that components could have offered different
configuration APIs with experimental features limited to alpha versions (for
example, sanitization offered only in a v1alpha1.KubeletConfiguration). Some
components could have decided to only use stable logging options.
In practice, this wasn't done. Furthermore, we don't want different components
to make different choices regarding which logging features they offer to
users. It should always be the same everywhere, for the sake of consistency.
This can be achieved with a saner Go API by dropping the distinction between
internal and external LoggingConfiguration types. Different stability levels of
indidividual fields have to be covered by documentation (done) and potentially
feature gates (not currently done).
Advantages:
- everything related to logging is under component-base/logs;
previously this was scattered across different packages and
different files under "logs" (why some code was in logs/config.go
vs. logs/options.go vs. logs/logs.go always confused me again
and again when coming back to the code):
- long-term config and command line API are clearly separated
into the "api" package underneath that
- logs/logs.go itself only deals with legacy global flags and
logging configuration
- removal of separate Go APIs like logs.BindLoggingFlags and
logs.Options
- LogRegistry becomes an implementation detail, with less code
and less exported functionality (only registration needs to
be exported, querying is internal)
These three options are the ones from logs.AddFlags which are not deprecated.
Therefore it makes sense to make them available also via the configuration file
support in the one command which currently supports that (kubelet).
Long-term, all commands should use LoggingConfiguration, either with a
configuration file (as in kubelet) or via flags (kube-scheduler,
kube-apiserver, kube-controller-manager).
Short-term, both approaches have to be supported. As the majority of the
commands only use logs.AddFlags, that function by default continues to register
the flags and only leaves that to Options.AddFlags when explicitly requested.
A drive-by bug fix is done for log flushing: the periodic flushing called
klog.Flush and therefore missed explicit flushing of the newer logr
backend. This bug was never present in any release Kubernetes and therefore the
fix is not submitted in a separate PR.
This implements the replacement of klog output to different files per level
with optionally splitting JSON output into two streams: one for info messages
on stdout, one for error messages on stderr. The info messages can get buffered
to increase performance. Because stdout and stderr might be merged by the
consumer, the info stream gets flushed before writing an error, to ensure that
the order of messages is preserved.
This also ensures that the following code pattern doesn't leak info messages:
klog.ErrorS(err, ...)
os.Exit(1)
Commands explicitly have to flush before exiting via logs.FlushLogs. Most
already do. But buffered info messages can still get lost during an unexpected
program termination, therefore buffering is off by default.
The new options get added to the v1alpha1 LoggingConfiguration with new command
line flags. Because it is an alpha field, changing it inside the v1beta kubelet
config should be okay as long as the fields are clearly marked as alpha.
* Use utilpointer to get a pointer
* Add tests for kubelet default configs
* Change copyright year from 2015 to 2021
* Run gofmt
* Add all negative and all positive test cases
* Change uses of whitelist to allowlist in kubelet sysctl
* Rename whitelist files to allowlist in Kubelet sysctl
* Further renames of whitelist to allowlist in Kubelet
* Rename podsecuritypolicy uses of whitelist to allowlist
* Update pkg/kubelet/kubelet.go
Co-authored-by: Danielle <dani@builds.terrible.systems>
Co-authored-by: Danielle <dani@builds.terrible.systems>
Files generate after running `make generated_files`.
Co-authored-by: Swati Sehgal <swsehgal@redhat.com>
Signed-off-by: Francesco Romani <fromani@redhat.com>
In this patch we enhance the kubelet configuration to support
cpuManagerPolicyOptions.
In order to introduce SMT-awareness in CPU Manager, we introduce a
new flag in Kubelet to allow the user to specify an additional flag
called `cpumanager-policy-options` to allow the user to modify the
behaviour of static policy to strictly guarantee allocation of whole
core.
Co-authored-by: Francesco Romani <fromani@redhat.com>
Signed-off-by: Swati Sehgal <swsehgal@redhat.com>
This adds the gate `SeccompDefault` as new alpha feature. Seccomp path
and field fallbacks are now passed to the helper functions, whereas unit
tests covering those code paths have been added as well.
Beside enabling the feature gate, the feature has to be enabled by the
`SeccompDefault` kubelet configuration or its corresponding
`--seccomp-default` CLI flag.
Signed-off-by: Sascha Grunert <sgrunert@redhat.com>
Apply suggestions from code review
Co-authored-by: Paulo Gomes <pjbgf@linux.com>
Signed-off-by: Sascha Grunert <sgrunert@redhat.com>
- Change the feature gate from alpha to beta and enable it by default
- Update a few of the unit tests due to feature gate being enabled by
default
- Small refactor in `nodeshutdown_manager` which adds `featureEnabled`
function (which checks that feature gate and that
`kubeletConfig.ShutdownGracePeriod > 0`).
- Use `featureEnabled()` to exit early from shutdown manager in the case
that the feature is disabled
- Update kubelet config defaulting to be explicit that
`ShutdownGracePeriod` and `ShutdownGracePeriodCriticalPods` default to
zero and update the godoc comments.
- Update defaults and add featureGate tag in api config godoc.
With this feature now in beta and the feature gate enabled by default,
to enable graceful shutdown all that will be required is to configure
`ShutdownGracePeriod` and `ShutdownGracePeriodCriticalPods` in the
kubelet config. If not configured, they will be defaulted to zero, and
graceful shutdown will effectively be disabled.
We will have two layers of the validation.
- the first part of the validation logic will be implemented under the
`ValidateKubeletConfiguration` method
- the second one that requires knowledge about machine topology and
node allocatable resources will be implemented under the memory manager.
Signed-off-by: Artyom Lukianov <alukiano@redhat.com>
