"
Currently all logical read operations are counted in a single pair of
metrics (successful/failed) located in the `database::db_stats`. This
prevents observing the number of reads executed against the
user/system
read semaphores. This distinction is especially interesting since
0c6bbc84c which selects the semaphore for each read based on the
scheduling group it is running under.
This mini series moves these counters into the semaphore and updates
the
exported metrics accordingly, the `total_reads` and
`total_reads_failed`
now has a user/system lable, just like the other semaphore dependent
metrics.
Tests: manual(checked that new metric works)
"
* 'per-semaphore-read-metrics/v2' of https://github.com/denesb/scylla:
database: move total_reads* metrics to the concurrency semaphore
database: setup_metrics(): split the registering database metrics in two
reader_concurrency_semaphore: add non-const stats accessor
reader_concurrency_semaphore: s/inactive_read_stats/stats/