Metrics v3 is mainly a reorganization of metrics into smaller groups of
metrics and the removal of internal aggregation of metrics received from
peer nodes in a MinIO cluster.
This change adds the endpoint `/minio/metrics/v3` as the top-level metrics
endpoint and under this, various sub-endpoints are implemented. These
are currently documented in `docs/metrics/v3.md`
The handler will serve metrics at any path
`/minio/metrics/v3/PATH`, as follows:
when PATH is a sub-endpoint listed above => serves the group of
metrics under that path; or when PATH is a (non-empty) parent
directory of the sub-endpoints listed above => serves metrics
from each child sub-endpoint of PATH. otherwise, returns a no
resource found error
All available metrics are listed in the `docs/metrics/v3.md`. More will
be added subsequently.
Currently, we read from `/proc/diskstats` which is found to be
un-reliable in k8s environments. We can read from `sysfs` instead.
Also, cache the latest drive io stats to find the diff and update
the metrics.
The previous logic of calculating per second values for disk io stats
divides the stats by the host uptime. This doesn't work in k8s
environment as the uptime is of the pod, but the stats (from
/proc/diskstats) are from the host.
Fix this by storing the initial values of uptime and the stats at the
timme of server startup, and using the difference between current and
initial values when calculating the per second values.
- Move RenameFile to websockets
- Move ReadAll that is primarily is used
for reading 'format.json' to to websockets
- Optimize DiskInfo calls, and provide a way
to make a NoOp DiskInfo call.
historically, we have always kept storage-rest-server
and a local storage API separate without much trouble,
since they both can independently operate due to no
special state() between them.
however, over some time, we have added state()
such as
- drive monitoring threads now there will be "2" of
them per drive instead of just 1.
- concurrent tokens available per drive are now twice
instead of just single shared, allowing unexpectedly
high amount of I/O to go through.
- applying serialization by using walkMutexes can now
be adequately honored for both remote callers and local
callers.
By default the cpu load is the cumulative of all cores. Capture the
percentage load (load * 100 / cpu-count)
Also capture the percentage memory used (used * 100 / total)
`resourceMetricsMap` has no protection against concurrent reads and writes.
Add a mutex and don't use maps from the last iteration.
Bug introduced in #18057Fixes#18271
Add a new endpoint for "resource" metrics `/v2/metrics/resource`
This should return system metrics related to drives, network, CPU and
memory. Except for drives, other metrics should have corresponding "avg"
and "max" values also.
Reuse the real-time feature to capture the required data,
introducing CPU and memory metrics in it.
Collect the data every minute and keep updating the average and max values
accordingly, returning the latest values when the API is called.
Aditya Manthramurthy
Praveen raj Mani
Harshavardhana
Shireesh Anjal
Klaus Post