This fixes two related tests to better test our "balanced" distribution algorithm.
The first test originally provided an input with the following number of CPUs
available on each NUMA node:
Node 0: 16
Node 1: 20
Node 2: 20
Node 3: 20
It then attempted to distribute 48 CPUs across them with an expectation that
each of the first 3 NUMA nodes would have 16 CPUs taken from them (leaving Node
0 with no more CPUs in the end).
This would have resulted in the following amount of CPUs on each node:
Node 0: 0
Node 1: 4
Node 2: 4
Node 3: 20
Which results in a standard deviation of 7.6811
However, a more balanced solution would actually be to pull 16 CPUs from NUMA
nodes 1, 2, and 3, and leave 0 untouched, i.e.:
Node 0: 16
Node 1: 4
Node 2: 4
Node 3: 4
Which results in a standard deviation of 5.1961524227066
To fix this test we changed the original number of available CPUs to start with
4 less CPUs on NUMA node 3, and 2 more CPUs on NUMA node 0, i.e.:
Node 0: 18
Node 1: 20
Node 2: 20
Node 3: 16
So that we end up with a result of:
Node 0: 2
Node 1: 4
Node 2: 4
Node 3: 16
Which pulls the CPUs from where we want and results in a standard deviation of 5.5452
For the second test, we simply reverse the number of CPUs available for Nodes 0
and 3 as:
Node 0: 16
Node 1: 20
Node 2: 20
Node 3: 18
Which forces the allocation to happen just as it did for the first test, except
now on NUMA nodes 1, 2, and 3 instead of NUMA nodes 0,1, and 2.
Signed-off-by: Kevin Klues <kklues@nvidia.com>
Previously these would return lists that were too long because we appended to
pre-initialized lists with a specific size.
Since the primary place these functions are used is in the mean and standard
deviation calculations for the NUMA distribution algorithm, it meant that the
results of these calculations were often incorrect.
As a result, some of the unit tests we have are actually incorrect (because the
results we expect do not actually produce the best balanced
distribution of CPUs across all NUMA nodes for the input provided).
These tests will be patched up in subsequent commits.
Signed-off-by: Kevin Klues <kklues@nvidia.com>
This was already possible before because the underlying errors.As supports
it. But because it wasn't clear, a lot of code unnecessarily checks for nil
before calling the Is* functions.
Right now, `run_remote.go` only supports GCE instances. But actually
running the tests is completely independent of GCE and could work just
as well on any SSH-accessible machine.
This patch adds a new `--mode` switch, which defaults to `gce` for
backwards compatibility, but can be set to `ssh`. In that mode, the GCE
API is not used at all, and we simply connect to the hosts given via
`--hosts`.
This is still better than `run_local.go` because the latter mixes build
environment with test environment, which doesn't fit well with
container-optimized operating systems.
This is part of an effort to setup the e2e node tests on Fedora CoreOS
(see https://github.com/coreos/fedora-coreos-tracker/issues/990).
Patch best viewed with whitespace ignored.
