[Named min timestamp leases] Add metric for number of locked timestamps #7406
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| static NamedMinTimestampTracker create(String timestampName, TimestampLeaseMetrics metrics) { | ||
| AtomicInteger numLocksHeld = new AtomicInteger(); | ||
| metrics.locksHeld().name(timestampName).build(numLocksHeld::get); |
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I left comments on this in #7400. The writes are synchronized through the object's intrinsic lock, and the get under the hood is a volatile read. Should I just make this a volatile?
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Yeah I think that's right, go for it
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Please write a description - I know this PR is about metrics, but that metric section of the review does also cover some things to think about where it's worth explicitly saying that yes, this is fine.
Otherwise, some naming bits but generally looks reasonable.
| docs: Number of locks held in timestamp trackers | ||
| type: gauge | ||
| tags: | ||
| - name |
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nit: timestampName or similar
Also, importantly, this means that we must not have a large number of timestamp names without breaking metrics infrastructure; how are we going to track that?
| timestampLease: | ||
| docs: Metrics tracking TimeLock's implementation of timestamp leases | ||
| metrics: | ||
| locksHeld: |
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Should trackers be aware of the concept of locks / is that an implementation detail? I'd be more inclined to say number of lease holders or similar...
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| static NamedMinTimestampTracker create(String timestampName, TimestampLeaseMetrics metrics) { | ||
| AtomicInteger numLocksHeld = new AtomicInteger(); | ||
| metrics.locksHeld().name(timestampName).build(numLocksHeld::get); |
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Yeah I think that's right, go for it
General
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==COMMIT_MSG==
==COMMIT_MSG==
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