The MacOS CI in github actions often hangs without any logs. GH argues that
it's due to resource utilization, either running out of disk space, memory, or CPU
starvation, and thus the runner is terminated.
This PR contains multiple attempts to resolve this:
1. introducing pause_process instead of SIGSTOP, which waits for the process
to stop before resuming the test, possibly resolving race conditions in some tests,
this was a suspect since there was one test that could result in an infinite loop in that
case, in practice this didn't help, but still a good idea to keep.
2. disable the `save` config in many tests that don't need it, specifically ones that use
heavy writes and could create large files.
3. change the `populate` proc to use short pipeline rather than an infinite one.
4. use `--clients 1` in the macos CI so that we don't risk running multiple resource
demanding tests in parallel.
5. enable `--verbose` to be repeated to elevate verbosity and print more info to stdout
when a test or a server starts.
There is a race condition in the test:
```
*** [err]: redis-cli --cluster add-node with cluster-port in tests/unit/cluster/cli.tcl
Expected '5' to be equal to '4' {assert_equal 5 [CI 0 cluster_known_nodes]} proc ::test)
```
When using cli to add node, there can potentially be a race condition
in which all nodes presenting cluster state o.k even though the added
node did not yet meet all cluster nodes.
This comment and the fix were taken from #11221. Also apply it in several
other similar places.
When using cli to add node, there can potentially be a race condition in
which all nodes presenting cluster state o.k even though the added node
did not yet meet all cluster nodes.
this adds another utility function to wait until all cluster nodes see the same cluster size
A timing issue like this was reported in freebsd daily CI:
```
*** [err]: Sanity test push cmd after resharding in tests/unit/cluster/cli.tcl
Expected 'CLUSTERDOWN The cluster is down' to match '*MOVED*'
```
We additionally wait for each node to reach a consensus on the cluster
state in wait_for_condition to avoid the cluster down error.
The fix just like #10495, quoting madolson's comment:
Cluster check just verifies the the config state is self-consistent,
waiting for cluster_state to be okay is an independent check that all
the nodes actually believe each other are healthy.
At the same time i noticed that unit/moduleapi/cluster.tcl has an exact
same test, may have the same problem, also modified it.
