When rapidly processing informer events it can happen that a pod gets scheduled
twice (seen only in the TestEviction/update unit test):
- Claim update observed, pod from informer cache with NodeName from update -> queue pod for eviction.
- Pod update observed, claim from informer cache -> queue pod again.
The effect is one additional Get call to the apiserver. We can avoid it by
maintaining an LRU cache with the UIDs of the pods which we have evicted and
thus don't need to do anything for.
In these cases it's certain that no time needs to pass, so Wait can
replace polling with Eventually. This also means that locking is
not necessary to prevent data races.
In particular with the builtin tCtx.Assert/Expect the assertions are also short
when using gomega and often more readable (no more confusion in Equal which one
is the expected and which the actual value).
We can observe the delay in the metric histogram. Because we run in a synctest
bubble, the delay is 100% predictable.
Unfortunately we cannot use the reactor mechanism of the fake client: that
delays while holding the fake's mutex. When some other goroutine (in this case,
the event recorder) calls the client, it gets blocked without being considered
durably blocked by synctest, so time does not advance and the test gets stuck.
Thanks for waiting for cache sync via channels the random delays caused by
polling are gone, making the initial setup including cache sync happen
"immediately" when a test starts (= same virtual time). This makes the tests
more predictable and simplifies making further assertions about when something
happens or how long it takes.
While at it, restore previous performance by setting feature gates once and
running tests in parallel again.
* DRA: support non-pod references in ReservedFor
Signed-off-by: MohammedSaalif <salifud2004@gmail.com>
* Expand reservation validation comment in syncClaim as suggested by mortent
* Address feedback: rename valid to remaining and remove obsolete TODO
---------
Signed-off-by: MohammedSaalif <salifud2004@gmail.com>
5644850607 added support for List+Watch to a fake client-go instance.
However, that support was not quite working yet as seen when analyzing a test
flake:
- List returned early when there were no objects, without adding the
ResourceVersion. The ResourceVersion should have been "0" instead.
- When encountering "" as ResourceVersion, Watch didn't deliver
any objects. That was meant to preserve compatibility with clients
which don't expect objects from a Watch, but the right semantic of
"" is "Start at most recent", which includes delivering existing
objects.
Tests which meddle with the List implementation via a reactor (like
clustertrustbundlepublisher) have to be aware that Watch now may
return objects when given an empty ResourceVersion.
This initially was attempted in 5f083e3b9f
but it caused e2e failing heavily (see
https://github.com/kubernetes/kubernetes/issues/135222 for more details).
The changes proposed in e6641cd290
clarified the naming of the two existing scale methods but they still
leave both of them as is.
This change goes a step further by combining both into a single method
with a parameter `forceUpdate` which is responsible for driving the mode
of execution between lazy update and a forced update.
Signed-off-by: Maciej Szulik <soltysh@gmail.com>
* DRA resource claim controller: configurable number of workers
It might never be necessary to change the default, but it is hard to be sure.
It's better to have the option, just in case.
* generate files
* resourceclaimcontroller: normalize validation error message
* Update cmd/kube-controller-manager/app/options/resourceclaimcontroller.go
Co-authored-by: Jordan Liggitt <jordan@liggitt.net>
---------
Co-authored-by: Patrick Ohly <patrick.ohly@intel.com>
Co-authored-by: Jordan Liggitt <jordan@liggitt.net>
Add unit test with a volume plugin that does not support SELinux. That
simulates a CSi driver whose spec.SELinuxMount is empty or false.
This requires a little refactoring, each unit test now has a flag if it
runs with a volume plugin that supports SELinux.
