# HStream Metrics
Table of metrics, and for usage, please refer to Monitoring chapter.
Note: For metrics with intervals, such as stats in categories like stream and subscription, users can specify intervals (default intervals [1min, 5min, 10min]). The smaller the interval, the closer it gets to the rate in real-time.
| Category | Metrics | Unit | Description |
|---|---|---|---|
| stream_counter | append_total | # | Total number of append requests of a stream |
| append_failed | # | Total number of failed append request of a stream | |
| stream | append_in_bytes | B/s | Rate of bytes received and successfully written to the stream. |
| append_in_records | #/s | Rate of records received and successfully written to the stream | |
| append_in_requests | #/s (QPS) | Rate of append requests received per stream | |
| append_failed_requests | #/s (QPS) | Rate of failed append requests received per stream | |
| subscription_counter | resend_records | # | Total number of resent records per subscription |
| subscription | send_out_bytes | B/s | Rate of bytes sent by the server per subscription |
| acks / acknowledgements | #/s | Rate of acknowledgements received per subscription | |
| request_messages | #/s | Rate of requests received from clients per subcription | |
| response_messages | #/s | Rate of response sent to clients per subscription |