# Statistics and information Shows information about process statistics (cache hits, internal queue sizes) and other information such as email queue size. ## halontop The *halontop* program shows a visual view of all counters with live updates and rates calculations.  The first line shows the process ID, `smtpd` process uptime and current host time. Values in blue show the difference between the previous value and the current value, e.g. +6, -6. Navigate between panes showing the following sections, using `<` `>` cursor keys. SERVERS : Name, number of inbound connections, percentage occupied. SCRIPTS : For each type of script hook, how many are running, finished, and pending to be executed. Also shows script errors, if any. The pre-delivery and post-delivery hooks are queue actions when delivering outbound messages. The others relate to phases of the inbound SMTP conversations. Non-zero numbers in the “pending” state show you have messages that cannot run the script hook yet. High counts can indicate the need for [Performance tuning](config_tuning.html.md). THREADS : The script thread activity broken down by thread pool name. “_default” and “_queues” are the standard names. LOADER : Count, pending and active counts. Messages coming into the queue, on a well running system will correlate with the injection rate. High “pending” values indicate a possible disk performance issue. QUOTA : Size. QUEUES : Active (priority 0 and 1), defer, hold, update and pending message counts. POLICIES / DYNAMIC : Count of suspends and conditions. PICKUP : Count of total messages picked up, skips, misses, pending and evals. POLICIES / CONCURRENCY : Outbound connection concurrency: suspends and counters. POLICIES / RATE : Outbound rate limiting: suspends and buckets. CONNECTIONS : Outbound connection concurrency, as a count and percentage of total. POOLING : Outbound connection pooling size, hits, misses, expires, evicts and skips. DELIVERY : Delivered, delayed and failed (since last restart). RELEASE : Pending count. RESOLVER : Running, pending and dedup counts. High “pending” counts may indicate a problem with DNS reolution. RESOLVER CACHE : Size, hits, misses, expires, evicts and skips. DOMAIN CACHE : Size, hits, misses, expires, and evicts. ## halonctl process-stats Text based output for counters may be extracted using *halonctl* suited for data collection. ```console $ halonctl process-stats process.pid: 48535 process.runtime: 3638 ... ``` Output can be native text (default), JSON or OpenMetrics format: ```console $ halonctl process-stats --help Show smtpd process information Usage: /opt/halon/bin/halonctl.bin process-stats [OPTIONS] Options: -h,--help Print this help message and exit --json Excludes: --openmetrics Dump response as JSON --json-request Dump request as JSON --openmetrics Excludes: --json Dump response as OpenMetrics ``` [OpenMetrics](https://openmetrics.io/) format can be used directly with monitoring tools such as [Prometheus](https://prometheus.io/) and [Kibana](https://www.elastic.co/kibana). The output is self-describing, with `# TYPE`, `# HELP` and `# UNIT` metadata directives; see [Metrics summary](openmetrics.html.md).