Recommended Metrics

Dovecot Proxy

Dovecot Backend

Email IO metrics

@metric_defaults = backend contains:

mail_read

Number of email GET requests to HTTP-based object storage. See http_request_finished.

mail_write

Number of email PUT requests to HTTP-based object storage. See http_request_finished.

mail_delete

Number of email DELETE requests to HTTP-based object storage. See http_request_finished.

FTS index IO/CPU metrics

fts_read

Number of FTS object GET requests to HTTP-based object storage, including size of the objects. See http_request_finished.

fts_write

Number of FTS object PUT requests to HTTP-based object storage, including size of the objects. See http_request_finished.

fts_delete

Number of FTS object DELETE requests to HTTP-based object storage. This is normally very close to fts_write. See http_request_finished.

indexer_worker_indexing_finished

Number of FTS indexing sessions, including the user space CPU usage. See indexer_worker_indexing_finished.

Index IO metrics

@metric_defaults = backend contains:

metacache_user_refresh_finished_refreshed_changed

Number of mail sessions where user's metacache was refreshed by listing index objects in storage, and new changes were found. See metacache_user_refresh_finished.

metacache_user_refresh_finished_refreshed_unchanged

Number of mail sessions where user's metacache was refreshed by listing index objects in storage, and metacache was already up-to-date. See metacache_user_refresh_finished.

metacache_mailbox_refresh_finished_refreshed_changed

Number of mailbox accesses where metacache was refreshed by listing index objects in storage, and new changes were found. See metacache_mailbox_refresh_finished.

metacache_mailbox_refresh_finished_refreshed_unchanged

Number of mailbox accesses where metacache was refreshed by listing index objects in storage, and metacache was already up-to-date. See metacache_mailbox_refresh_finished.

metacache_user_bundle_upload_finished

Number of user index bundle uploads and the bundle sizes, grouped by bundle type. See metacache_user_bundle_upload_finished.

metacache_mailbox_bundle_upload_finished

Number of mailbox index bundle uploads and the bundle sizes, grouped by bundle type. See metacache_user_bundle_upload_finished.

metacache_user_clean_finished

Number of metacache cleans, grouped by min_priority. If you see these metrics grow much higher than usual, metacache may be too small. See metacache_user_clean_finished.

obox_mailbox_rescan_finished

Number of mailbox accesses resulting in listing mail objects in storage. See obox_mailbox_rescan_finished.

obox_mailbox_rebuild_finished

Number of mailbox accesses resulting in rebuilding the mailbox index, including listing mail objects in storage. See obox_mailbox_rebuild_finished.

Cluster specific events

@metric_defaults = backend contains:

cluster_group_move_finished

Number of user group moves (to another backend) successfully finished. See cluster_user_group_move_finished.

cluster_group_move_failed

Number of user group moves failed. See cluster_user_group_move_finished.

cluster_user_move_finished

Number of user moves (to another group/site) successfully finished. See cluster_user_move_finished.

cluster_user_move_finished

Number of user moves failed. See cluster_user_move_finished.

Detailed mail access and delivery metrics

metric imap_commands {
  filter = event=imap_command_finished
  group_by tagged_reply_state {
  }
  group_by cmd_name {
  }
}
metric imap_commands_slow {
  # In some installations there may be too many slow commands to be worth logging these
  exporter = log-export
  filter = event=imap_command_finished AND (NOT cmd_name=IDLE) AND duration > 1min
}
metric lmtp_commands {
  filter = event=smtp_server_command_finished AND protocol=lmtp
  group_by cmd_name {
  }
}
metric push_notifications {
  filter = event=push_notification_finished
}
metric sieve_actions {
  filter = event=sieve_action_finished
  group_by action_name {
  }
}
metric smtp_commands {
  filter = event=smtp_server_command_finished AND protocol=smtp
  group_by cmd_name {
  }
}
metric unknown_commands {
  exporter = log-export
  filter = (event=imap_command_finished OR event=smtp_server_command_finished) AND cmd_name=unknown
}

See also:

• imap_command_finished,
• push_notification_finished,
• sieve_action_finished,
• smtp_server_command_finished,
• smtp_server_command_finished and

Events to catch bugs/problems

INFO

The following events are usually logged as errors/warnings in any case, thus the log-export will likely cause duplicate logging. However, they may be easier to parse and may provide additional details.

metric fs_dictmap_dict_write_uncertain {
  filter = event=fs_dictmap_dict_write_uncertain AND (NOT cleanup=failed)
  exporter = log-export
}
metric fs_dictmap_dict_write_uncertain_failed {
  filter = event=fs_dictmap_dict_write_uncertain AND cleanup=failed
  exporter = log-export
}
metric fs_dictmap_object_lost {
  filter = event=fs_dictmap_object_lost
  exporter = log-export
  # Note: file_type=fts is only in v2.3.15+
  group_by file_type {
  }
}
metric fs_dictmap_max_bucket_changed_iter {
  filter = event=fs_dictmap_max_bucket_changed AND reason=iter
  exporter = log-export
}
metric fts_dovecot_too_many_triplets {
  # v2.3.15+
  filter = event=fts_dovecot_too_many_triplets
  exporter = log-export
}
metric mail_cache_new_field_indexed {
  # Helps to find out if mail clients start fetching a new header
  filter = event=mail_cache_decision_changed AND reason=add
  # If growth is detected, export the events to find out what header is added:
  #exporter = log-export
}
metric metacache_pull_finished {
    exporter = log-export
    filter = event=metacache_pull_finished and error=""
    group_by type {
    }
}
metric metacache_pull_finished_failure {
   exporter = log-export
   filter = event=metacache_pull_finished and not error=""
   group_by type {
   }
}

See also:

• fs_dictmap_dict_write_uncertain,
• fs_dictmap_max_bucket_changed,
• fs_dictmap_object_lost,
• fts_dovecot_too_many_triplets,
• mail_cache_decision_changed and
• metacache_pull_finished.