# Gerrit Code Review - Metrics

version v2.13.8-15-gfb82721

Metrics about Gerrit’s internal state can be sent to external monitoring systems via plugins. See the plugin documentation for details of plugin implementations.

## Metrics

The following metrics are reported.

### General

- `build/label`: Version of Gerrit server software.

- `events`: Triggered events.

### Process

- `proc/birth_timestamp`: Time at which the Gerrit process started.

- `proc/uptime`: Uptime of the Gerrit process.

- `proc/cpu/usage`: CPU time used by the Gerrit process.

- `proc/num_open_fds`: Number of open file descriptors.

- `proc/jvm/memory/heap_committed`: Amount of memory guaranteed for user objects.

- `proc/jvm/memory/heap_used`: Amount of memory holding user objects.

- `proc/jvm/memory/non_heap_committed`: Amount of memory guaranteed for classes, etc.

- `proc/jvm/memory/non_heap_used`: Amount of memory holding classes, etc.

- `proc/jvm/memory/object_pending_finalization_count`: Approximate number of objects needing finalization.

- `proc/jvm/gc/count`: Number of GCs.

- `proc/jvm/gc/time`: Approximate accumulated GC elapsed time.

- `proc/jvm/thread/num_live`: Current live thread count.

### Caches

- `caches/memory_cached`: Memory entries.

- `caches/memory_hit_ratio`: Memory hit ratio.

- `caches/memory_eviction_count`: Memory eviction count.

- `caches/disk_cached`: Disk entries used by persistent cache.

- `caches/disk_hit_ratio`: Disk hit ratio for persistent cache.

### HTTP

- `http/server/error_count`: Rate of REST API error responses.

- `http/server/success_count`: Rate of REST API success responses.

- `http/server/rest_api/count`: Rate of REST API calls by view.

- `http/server/rest_api/error_count`: Rate of REST API calls by view.

- `http/server/rest_api/server_latency`: REST API call latency by view.

- `http/server/rest_api/response_bytes`: Size of REST API response on network (may be gzip compressed) by view.

### Query

- `query/query_latency`: Successful query latency, accumulated over the life of the process.

### SSH sessions

- `sshd/sessions/connected`: Number of currently connected SSH sessions.

- `sshd/sessions/created`: Rate of new SSH sessions.

- `sshd/sessions/authentication_failures`: Rate of SSH authentication failures.

### SQL connections

- `sql/connection_pool/connections`: SQL database connections.

### JGit

- `jgit/block_cache/cache_used`: Bytes of memory retained in JGit block cache.

- `jgit/block_cache/open_files`: File handles held open by JGit block cache.

### Git

- `git/upload-pack/request_count`: Total number of git-upload-pack requests.

- `git/upload-pack/phase_counting`: Time spent in the 'Counting…​' phase.

- `git/upload-pack/phase_compressing`: Time spent in the 'Compressing…​' phase.

- `git/upload-pack/phase_writing`: Time spent transferring bytes to client.

- `git/upload-pack/pack_bytes`: Distribution of sizes of packs sent to clients.

### NoteDb

- `notedb/update_latency`: NoteDb update latency by table.

- `notedb/stage_update_latency`: Latency for staging updates to NoteDb by table.

- `notedb/read_latency`: NoteDb read latency by table.

- `notedb/parse_latency`: NoteDb parse latency by table.

- `notedb/auto_rebuild_latency`: NoteDb auto-rebuilding latency by table.

- `notedb/auto_rebuild_failure_count`: NoteDb auto-rebuilding attempts that failed by table.

### Replication Plugin

- `plugins/replication/replication_latency`: Time spent pushing to remote destination.

- `plugins/replication/replication_delay`: Time spent waiting before pushing to remote destination.

- `plugins/replication/replication_retries`: Number of retries when pushing to remote destination.

Part of Gerrit Code Review