This PR adds counter metrics for the CPU system and the Geth process.
Currently the only metrics available for these items are gauges. Gauges are
fine when the consumer scrapes metrics data at the same interval as Geth
produces new values (every 3 seconds), but it is likely that most consumers
will not scrape that often. Intervals of 10, 15, or maybe even 30 seconds
are probably more common.
So the problem is, how does the consumer estimate what the CPU was doing in
between scrapes. With a counter, it's easy ... you just subtract two
successive values and divide by the time to get a nice, accurate average.
But with a gauge, you can't do that. A gauge reading is an instantaneous
picture of what was happening at that moment, but it gives you no idea
about what was going on between scrapes. Taking an average of values is
meaningless.
This changes how we read performance metrics from the Go runtime. Instead
of using runtime.ReadMemStats, we now rely on the API provided by package
runtime/metrics.
runtime/metrics provides more accurate information. For example, the new
interface has better reporting of memory use. In my testing, the reported
value of held memory more accurately reflects the usage reported by the OS.
The semantics of metrics system/memory/allocs and system/memory/frees have
changed to report amounts in bytes. ReadMemStats only reported the count of
allocations in number-of-objects. This is imprecise: 'tiny objects' are not
counted because the runtime allocates them in batches; and certain
improvements in allocation behavior, such as struct size optimizations,
will be less visible when the number of allocs doesn't change.
Changing allocation reports to be in bytes makes it appear in graphs that
lots more is being allocated. I don't think that's a problem because this
metric is primarily interesting for geth developers.
The metric system/memory/pauses has been changed to report statistical
values from the histogram provided by the runtime. Its name in influxdb has
changed from geth.system/memory/pauses.meter to
geth.system/memory/pauses.histogram.
We also have a new histogram metric, system/cpu/schedlatency, reporting the
Go scheduler latency.
This changes the CI / release builds to use the latest Go version. It also
upgrades golangci-lint to a newer version compatible with Go 1.19.
In Go 1.19, godoc has gained official support for links and lists. The
syntax for code blocks in doc comments has changed and now requires a
leading tab character. gofmt adapts comments to the new syntax
automatically, so there are a lot of comment re-formatting changes in this
PR. We need to apply the new format in order to pass the CI lint stage with
Go 1.19.
With the linter upgrade, I have decided to disable 'gosec' - it produces
too many false-positive warnings. The 'deadcode' and 'varcheck' linters
have also been removed because golangci-lint warns about them being
unmaintained. 'unused' provides similar coverage and we already have it
enabled, so we don't lose much with this change.
This enables the following linters
- typecheck
- unused
- staticcheck
- bidichk
- durationcheck
- exportloopref
- gosec
WIth a few exceptions.
- We use a deprecated protobuf in trezor. I didn't want to mess with that, since I cannot meaningfully test any changes there.
- The deprecated TypeMux is used in a few places still, so the warning for it is silenced for now.
- Using string type in context.WithValue is apparently wrong, one should use a custom type, to prevent collisions between different places in the hierarchy of callers. That should be fixed at some point, but may require some attention.
- The warnings for using weak random generator are squashed, since we use a lot of random without need for cryptographic guarantees.
This PR adds flag to enable InfluxDB v2 (--metrics.influxdbv2), flags for v2-specific features (--metrics.influxdb.token, --metrics.influxdb.bucket), also carries over addition of support for specifying organization (--metrics.influxdb.organization), but still retains backwards compatibility with InfluxDB v1.
turboboost55
ucwong
Felix Lange
Delweng
Martin Holst Swende
rjl493456442
jwasinger
Péter Szilágyi
Guillaume Ballet
Anton Evangelatov
Elad