Sharing the same client between updater threads virtually serializes
access, in practice making the effective parallelism close to 1.
With this patch, in my bench cluster of 300 nodes, the time taken by
updating all nodes drops from ~2 minutes to ~12 seconds (with the
default parallelism of 10 node updater threads). This demonstrates the
10-fold increased parallelism from ~1 to 10.
There might be other solutions that could be explored, e.g. caching
nodes with an indexer/lister but otoh nfd doesn't necessarily need/want
to watch every little change in each node. We only need to get the node
when something in our own CRDs change (we don't react to any changes in
the node object itself). Using multiple clients was the most obvious
choice to solve the problem for now.
Prevents potential race between node-updater pool and the api-controller
when re-configuring nfd-master. Reconfiguration causes a new
api-controller instance to be created so nfd api lister might change in
the midst of processing a node update (if the pool was running). No
actual issues related to this have been identified but races (like this)
should still be avoided.
Don't try to be too smart when kubeconfig is needed. In practice, the
nfd-master really doesn't work anymore (with the NodeFeature API
enabled) without a kubeconfig set. This patch fixes crashes happening
when NoPublish is enabled, e.g. in listing all nodes in the nfd api
handler and in getting single node objects in the node updater pool.
This patch changes the kubeconfig parsing to happen at the creation of
the nfd-master instance. We don't need to do that at reconfigure time as
none of the dynamic config options affect it. Unit tests are adjusted,
accordingly.
This started as a small effort to simplify the usage of "ready" channel
in nfd-master. It extended into a wider simplification/unification of
the channel usage.
Change the handling of LabelWhiteList config option to use a pointer to
detect when the option is unset. This doesn't fix any detected crash but
is merely general improvement and stabilization, serving easier testing.
Also, use the regexp type from the core libs for the config struct -
dropping the unmasrhalling code for our custom regexp type - as the core
regexp now implements unmarshaller itself.
Prevent excess queries of node objects from the Kubernetes apiserver.
This significantly speeds up node updates (and reduces the load on the
apiserver) as the client-side throttling (which is good) does not bite
us that hard.
Prevents races when (re-)starting the queue. There are no reports on
issues related to this (and I haven't come up with any actual failure
path in the current code) but better to be safe and follow the best
practices.
Prevents (rare) races on nfd-master reconfigurartion. Previously the
scheme was registered at nfd API controller creation/startup time. This
caused a race with some lister/informer goroutines of the previous
(stoppped) controller still running and accessing (reading) the sceme
while we were updating (writing) it.
Treat node updates like a reconciliation loop. Keep trying on node
update as long as it fails. Node update permafailing likely indicates a
bug in the nfd code (there should be no reason for it to fail forever)
and it's better to clearly see it in the logs/metrics rather than giving
up after a few retries.
Fixes a memory leak that happened when stopping (and then re-starting)
the nfd api controller. The stop channel was not used properly which
caused the underlying informer to keep on running.
Correctly patch the "status" subresource. This got broken when
refactoring the code in 7a050e7cf9 and
wasn't even catched by the unit tests as the fake kubernetes client
doesn't handle subresources as the real apiserver does.
Implement some of frequently used helper functions inpackage.
This patch also contains big changes to the nfd-master unit tests. Much
of this is about migrating from the mocked apihelper interface to fake
kubernetes client that provides a bit more apiserver'ish functionality.
At the same time there is quite a bit of renaming in the tests,
shortening and unifying naming and getting rid of the extensive usage of
"mock" everywhere.
This change is part of an effort to remove the pkg/apihelper package.
GetKubeconfig is useful helper functionality shared accross the codebase
so move it into a "safe" location.
This patch separates the gRPC health server from the deprecated gRPC
server (disabled by default, replaced by the NodeFeature CRD API) used
for node labeling requests. The new health server runs on hardcoded TCP
port number 8082.
The main motivation for this change is to make the Kubernetes' built-in
gRPC liveness probes to function if TLS is enabled (as they don't
support TLS).
The health server itself is a naive implementation (as it was before),
basically only checking that nfd-master has started and hasn't crashed.
The patch adds a TODO note to improve the functionality.
Add new autoDefaultNs (default is "true") config option to nfd-master.
Setting the config option to false stops NFD from automatically adding
the "feature.node.kubernetes.io/" prefix to labels, annotations and
extended resources. Taints are not affected as for them no prefix is
automatically added. The user-visible part of enabling the option change
is that NodeFeatureRules, local feature files, hooks and configuration
of the "custom" may need to be altereda (if the auto-prefixing is
relied on).
For now, the config option defaults to "true", meaning no change in
default behavior. However, the intent is to change the default to
"false" in a future release, deprecating the option and eventually
removing it (forcing it to "false").
The goal of stopping doing "auto-prefixing" is to simplify the operation
(of nfd and users). Make the naming more straightforward and easier to
understand and debug (kind of WYSIWYG), eliminating peculiar corner
cases:
1. Make validation simpler and unambiguous
2. Remove "overloading" of names, i.e. the mapping two values to the
same actual name. E.g. previously something like
labels:
feature.node.kubernetes.io/foo: bar
foo: baz
Could actually result in node label:
feature.node.kubernetes.io/foo: baz
3. Make the processing/usagee of the "rule.matched" and "local.labels"
feature in NodeFeatureRules unambiguous and more understadable. E.g.
previously you could have node label
"feature.node.kubernetes.io/local-foo: bar" but in the NodeFeatureRule
you'd need to use the unprefixed name "local-foo" or the fully
prefixed name, depending on what was specified in the feature file (or
hook) on the node(s).
NOTE: setting autoDefaultNs to false is a breaking change for users who
rely on automatic prefixing with the default feature.node.kubernetes.io/
namespace. NodeFeatureRules, feature files, hooks and custom rules
(configuration of the "custom" source of nfd-worker) will need to be
altered. Unprefixed labels, annoations and extended resources will be
denied by nfd-master.
Make the handling of unprefixed names (of labels, annotations and
extended resources) well-defined and predictable. Previously the
resulting output was not predictable in case the same name was coming in
both the unprefixed and prefixed form, say unprefixed "foo=bar" coming from
one source (be it nfd-worker or NodeFeature(Rule)) and
"feature.node.kubernetes.io/foo=baz" from a NodeFeature(Rule).
Previously the output value was randomly either "bar" or "baz".
This patch adds prefixes to all names early in the processing
"pipeline", preventing random name clashes later on.
This patch addresses issues with slow node status (extended resources)
updates. Previously we did just a few retries in quick succession which
could result in the node update failing, just because node status was
updated slower than our retry window. The patch mitigates the issue by
increasing the number of tries to 15. In addition, it creates a
ratelimiter with a longer per-item (per-node) base delay.
The patch also fixes the e2e-tests to expose the issue.
We now have metrics for getting detailed information about the NFD
instances running. There should be no need to pollute the node object
with NFD version annotations.
One problem with the annotations also that they were incomplete in the
sense that they only covered nfd-master and nfd-worker but not
nfd-topology-updater or nfd-gc.
Also, there was a problem with stale annotations, giving misleading
information. E.g. there was no way to remove old/stale master.version
annotations if nfd-master was scheduled on another node where it was
previously running.
Add a counter for total number of node update/sync requests. In
practice, this counts the number of gRPC requests received if the gRPC
API is in use. If the NodeFeature API is enabled, this counts the
requests initiated by the NFD API controller, i.e. updates triggered by
changes in NodeFeature or NodeFeatureRule objects plus updates initiated
by the controller resync period.
Add a counter for errors encountered when processing NodeFeatureRules.
Another simple counter without any additional prometheus labels -
nfd-master logs can provide further details.
Add a new counter for tracking node update failures from nfd-master.
This tracks both normal feature updates and the --prune sub-command.
This is a simple counter without any additional labels - nfd-master logs
can be used for further diagnostics.
