Summary:
This sets up the counters that will allow us to expose the number
of pending FUSE requests in Eden top.
As D20846826 mentions adding metrics for FUSE request gives
visibility into fuse requests and overall health of eden.
This provides more insight beyond the metrics for live FUSE requests
since it shows the kernels view of FUSE requests. Looking at the difference
between the number of pending and live request, can identify issues
that arise at the interface between eden and FUSE and monitor how
quickly fuse workers are processing requests.
**note**: this is only for linux since macos has no equivalent to
`/sys/fs/fuse/connections`
Reviewed By: chadaustin
Differential Revision: D21074489
fbshipit-source-id: c0951f0dfd4fa764be28d8686d08cd0dd807db37
Summary:
Tl;DR Reduces costs of fuse request mertics by reducing lock contention.
D20922194 adds tracking for FUSE request metrics, this makes tracking those
metrics more efficient. Since every user request goes through the FUSE channel,
we want to reduce the cost of these metrics as much as possible (originally
mentioned in a comment D20922194).
The synchronization used to track the metrics is costly especially
when the lock is contended.
To reduce the cost, each FuseChannel will have a thread local copy of metrics.
Each will still be synchronized to allow for reading the metrics and for
Requests moved to other threads that will need to access the metrics. However,
the lock should be contended less often since only requests from a single fuse
channel thread will access it.
Reviewed By: chadaustin
Differential Revision: D21043792
fbshipit-source-id: ce58a0cbce334095976233bfac7578d39c81bb55
Summary:
This exposes metrics for the live FUSE requests (the duration
of the longest outstanding request and the number of outstanding
requests).
Because FUSE is the interface through which the user mostly interacts
with the file system they provide good metrics to judge if the perfomance
of eden is normal, or there may be an issue.
Exposing these counters this way will send them to ods, so it will not only
allow for debuging current issues, but can be used to look back at previous
problems. This data could also be used for alerting or more proactive
remediation.
Metrics are exposed per checkout to allow seeing which checkout was
having issues. This data will aggregated in `eden top` to be used as
an overall health indicator, but should more information be needed it
will be logged in ods.
Reviewed By: chadaustin
Differential Revision: D20922194
fbshipit-source-id: 16208883417acb77b62bf712cfdd9068c5420303
Summary:
This sets up the counters that will allow us to expose metrics for
live FUSE requests in Eden top.
This will allow us to track the number of live FUSE requests and the duration
of the longest FUSE request. If the duration of the longest FUSE request has
become very long, the number of FUSE requests is stuck at some value or
increasingly growing these can indicate there is a problem with the Fuse Channel
or something effecting this.
This provides more insight beyond the metrics for imports since many of the
FUSE requests will not cause imports, so this monitors more functionality.
Further because all user interaction with the filesystem goes through FUSE,
these metrics will give a good overall indication weather Eden is performing
normally.
Reviewed By: chadaustin
Differential Revision: D20846826
fbshipit-source-id: 34d834d193833a3c91d95fbb87361ddd863f64ca
Summary:
As mentioned in D20629833, adding metrics for live
imports in `eden top` gives more transparency to the
imports process and makes identifying import related
issues easier. This is set up to expose metrics for live
imports like those for pending imports in `eden top`.
Similar to D20611728 exposing this via these counters
will log this data. Having this data persisted will allow
tracking the performance of imports, and does the set
up for more pro-active fixing of issues. Further we can
look back to see issues that are no longer occurring, but
still of interest.
This also refactors the registration code so that it requires
no copy pasting to add a new counter. Avoiding copy paste
errors when adding more counters and making it easier to
maintain.
Reviewed By: chadaustin
Differential Revision: D20630813
fbshipit-source-id: 8a7a2a0135c7b7a5cde960b84dcb434c6c99eaeb
