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.
