This commit adds support for OpenCensus tracing
and metrics collection. This required support for
context.Context propogation throughout the cluster
codebase, and in particular, the ipfscluster component
interfaces.
The tracing propogates across RPC and HTTP boundaries.
The current default tracing backend is Jaeger.
The metrics currently exports the metrics exposed by
the opencensus http plugin as well as the pprof metrics
to a prometheus endpoint for scraping.
The current default metrics backend is Prometheus.
Metrics are currently exposed by default due to low
overhead, can be turned off if desired, whereas tracing
is off by default as it has a much higher performance
overhead, though the extent of the performance hit can be
adjusted with smaller sampling rates.
License: MIT
Signed-off-by: Adrian Lanzafame <adrianlanzafame92@gmail.com>
The disk informer uses "ipfs repo stat" to fetch the RepoSize value and
uses it as a metric.
The numpinalloc allocator is now a generalized ascendalloc which
sorts metrics in ascending order and return the ones with lowest
values.
License: MIT
Signed-off-by: Hector Sanjuan <hector@protocol.ai>