This exporter extracts statistics from group instances and exports as Prometheus metrics.

import (
	"github.com/mailgun/groupcache/v2"
	"github.com/mailgun/groupcache/v2/promexporter"
	"github.com/prometheus/client_golang/prometheus"
)

// ...

collector := promexporter.NewExporter()
prometheus.MustRegister(collector)

// Collector will discover newly created group.
group := groupcache.NewGroup("mygroup", cacheSize, getter)

• groupcache_cache_bytes{group,type="main|hot"}: Gauge of current bytes in use
• groupcache_cache_evictions_nonexpired_total{group,type="main|hot"}: Count of cache evictions for non-expired keys due to memory full
• groupcache_cache_evictions_total{group,type="main|hot"}: Count of cache evictions
• groupcache_cache_gets_total{group,type="main|hot"}: Count of cache gets
• groupcache_cache_hits_total{group,type="main|hot"}: Count of cache hits
• groupcache_cache_items{group,type="main|hot"}: Gauge of current items in use

• groupcache_get_from_peers_latency_lower{group}: Represent slowest duration to request value from peers
• groupcache_gets_total{group}: Count of cache gets (including from peers, from either main or hot caches)
• groupcache_hits_total{group}: Count of cache hits (from either main or hot caches)
• groupcache_loads_deduped_total{group}: Count of loads after singleflight
• groupcache_loads_total{group}: Count of (gets - hits)
• groupcache_local_load_errs_total{group}: Count of load errors from local cache
• groupcache_local_loads_total{group}: Count of loads from local cache
• groupcache_peer_errors_total{group}: Count of errors from peers
• groupcache_peer_loads_total{group}: Count of loads or cache hits from peers
• groupcache_server_requests_total{group}: Count of gets received from peers

This package source originated from https://github.com/udhos/groupcache_exporter. See LICENSE for MIT license details impacting the contents of this package directory in addition to the LICENSE at the root of this repo for co-existing Apache license details.