delta/go-git.git/src/runtime/metrics, branch dev.cmdgo

runtime/metrics: add additional allocation metrics

2021-04-29T21:54:05+00:00

This change adds four additional metrics to the runtime/metrics package
to fill in a few gaps with runtime.MemStats that were overlooked. The
biggest one is TotalAlloc, which is impossible to find with the
runtime/metrics package, but also add a few others for convenience and
clarity. For instance, the total number of objects allocated and freed
are technically available via allocs-by-size and frees-by-size, but it's
onerous to get them (one needs to sum the sample counts in the
histograms).

The four additional metrics are:
- /gc/heap/allocs:bytes   -- total bytes allocated (TotalAlloc)
- /gc/heap/allocs:objects -- total objects allocated (Mallocs - [tiny])
- /gc/heap/frees:bytes    -- total bytes frees (TotalAlloc-HeapAlloc)
- /gc/heap/frees:objects  -- total objects freed (Frees - [tiny])

This change also updates the descriptions of allocs-by-size and
frees-by-size to be more precise.

Change-Id: Iec8c1797a584491e3484b198f2e7f325b68954a7
Reviewed-on: https://go-review.googlesource.com/c/go/+/312431
Reviewed-by: Michael Pratt 
Trust: Michael Knyszek 
Run-TryBot: Michael Knyszek 
TryBot-Result: Go Bot

runtime/metrics: add tiny allocs metric

2021-04-27T13:59:22+00:00

Currently tiny allocations are not represented in either MemStats or
runtime/metrics, but they're represented in MemStats (indirectly) via
Mallocs. Add them to runtime/metrics by first merging
memstats.tinyallocs into consistentHeapStats (just for simplicity; it's
monotonic so metrics would still be self-consistent if we just read it
atomically) and then adding /gc/heap/tiny/allocs:objects to the list of
supported metrics.

Change-Id: Ie478006ab942a3e877b4a79065ffa43569722f3d
Reviewed-on: https://go-review.googlesource.com/c/go/+/312909
Trust: Michael Knyszek 
Run-TryBot: Michael Knyszek 
TryBot-Result: Go Bot 
Reviewed-by: Michael Pratt

runtime,runtime/metrics: add metric to track scheduling latencies

2021-04-23T13:48:10+00:00

This change adds a metric to track scheduling latencies, defined as the
cumulative amount of time a goroutine spends being runnable before
running again. The metric is an approximations and samples instead of
trying to record every goroutine scheduling latency.

This change was primarily authored by mknyszek@google.com.

Change-Id: Ie0be7e6e7be421572eb2317d3dd8dd6f3d6aa152
Reviewed-on: https://go-review.googlesource.com/c/go/+/308933
Trust: Michael Pratt 
Run-TryBot: Michael Pratt 
TryBot-Result: Go Bot 
Reviewed-by: Michael Knyszek

runtime/metrics: update documentation to current interface

2021-02-16T16:26:30+00:00

The package documentation referenced sample metadata that was removed in CL 282632. Update this documentation to be less specific
about what metadata is available.

Additionally, the documentation on the Sample type referred to Descriptions instead of All as the source of metrics names.

Fixes #44280.

Change-Id: I24fc63a744bf498cb4cd5bda56c1599f6dd75929
Reviewed-on: https://go-review.googlesource.com/c/go/+/292309
Reviewed-by: Michael Knyszek 
Trust: Michael Knyszek 
Trust: Dmitri Shuralyov 
Run-TryBot: Michael Knyszek 
TryBot-Result: Go Bot

runtime/metrics: fix a couple of documentation typpos

2021-02-09T02:00:01+00:00

Fixes #44150

Change-Id: Ibe5bfba01491dd8c2f0696fab40a1673230d76e9
Reviewed-on: https://go-review.googlesource.com/c/go/+/290349
Trust: Ian Lance Taylor 
Run-TryBot: Ian Lance Taylor 
TryBot-Result: Go Bot 
Reviewed-by: Dmitri Shuralyov 
Reviewed-by: Michael Knyszek

runtime/metrics: fix panic in readingAllMetric example

2021-02-08T16:09:01+00:00

medianBucket can return if the total is greater than thresh.
However, if a histogram has no counts, total and thresh
will both be zero and cause panic.

Adding an equal sign to prevent the potential panic.

Fixes #44148

Change-Id: Ifb8a781990f490d142ae7c035b4e01d6a07ae04d
Reviewed-on: https://go-review.googlesource.com/c/go/+/290171
Trust: Ian Lance Taylor 
Reviewed-by: Michael Knyszek 
Run-TryBot: Michael Knyszek 
TryBot-Result: Go Bot

runtime/metrics: mark histogram metrics as cumulative

2021-01-08T18:15:53+00:00

All the current histogram metrics accumulate counts from program start
to infinity, and can be reasonably used to compute rates (also to
generate windowed distributions).

Change-Id: I5196c59867de34fba41bb8552606fa315460cef9
Reviewed-on: https://go-review.googlesource.com/c/go/+/282633
Run-TryBot: Michael Knyszek 
TryBot-Result: Go Bot 
Trust: Michael Knyszek 
Reviewed-by: Michael Pratt 
Reviewed-by: Austin Clements

runtime/metrics: remove unused StopTheWorld Description field

2021-01-08T18:15:43+00:00

This change removes the as-of-yet unused StopTheWorld field in the
Description struct. Adding a new field to a struct is much easier than
removing it, so let's save it for when we actually need it.

Change-Id: I8074b8569187c1a148500575fa8a661534e875d5
Reviewed-on: https://go-review.googlesource.com/c/go/+/282632
Run-TryBot: Michael Knyszek 
TryBot-Result: Go Bot 
Trust: Michael Knyszek 
Reviewed-by: Michael Pratt 
Reviewed-by: Austin Clements

runtime/metrics: change unit on *-by-size metrics to match bucket unit

2021-01-08T16:28:15+00:00

This change modifies the *-by-size metrics' units to be based off the
bucket's unit (bytes) as opposed to the unit of the counts (objects).
This convention is more in-line with distributions in other metrics
systems.

Change-Id: Id3b68a09f52f0e1ff9f4346f613ae1cbd9f52f73
Reviewed-on: https://go-review.googlesource.com/c/go/+/282352
Run-TryBot: Michael Knyszek 
TryBot-Result: Go Bot 
Reviewed-by: Austin Clements 
Reviewed-by: Michael Pratt 
Trust: Michael Knyszek

runtime,runtime/metrics: use explicit histogram boundaries

2021-01-08T03:43:44+00:00

This change modifies the semantics of
runtime/metrics.Float64Histogram.Buckets to remove implicit buckets to
that extend to positive and negative infinity and instead defines all
bucket boundaries as explicitly listed.

Bucket boundaries remain the same as before except
/gc/heap/allocs-by-size:objects and /gc/heap/frees-by-size:objects no
longer have a bucket that extends to negative infinity.

This change simplifies the Float64Histogram API, making it both easier
to understand and easier to use.

Also, add a test for allocs-by-size and frees-by-size that checks them
against MemStats.

Fixes #43443.

Change-Id: I5620f15bd084562dadf288f733c4a8cace21910c
Reviewed-on: https://go-review.googlesource.com/c/go/+/281238
Run-TryBot: Michael Knyszek 
TryBot-Result: Go Bot 
Reviewed-by: Austin Clements 
Reviewed-by: Michael Pratt 
Trust: Michael Knyszek