Meta Metrics¶

Introduction¶

Currently, Nebula Graph supports obtaining the basic performance metrics for the meta service via HTTP.

Each performance metric consists of three parts, namely <counter_name>.<statistic_type>.<time_range>.

Counter Names¶

Each counter name is composed of the interface name and the counter name. Meta service only counts the heartbeat. Currently, the supported interfaces are:

meta_heartbeat_qps
meta_heartbeat_error_qps
meta_heartbeat_latency

Statistics Type¶

Currently supported types are SUM, COUNT, AVG, RATE and P quantiles (P99, P999, ..., P999999). Among which:

• Metrics have suffixes _qps and _error_qps support SUM, COUNT, AVG, RATE but don't support P quantiles.
• Metrics have suffixes _latency support SUM, COUNT, AVG, RATE, and P quantiles.

Time Range¶

Currently, the supported time ranges are 60s, 600s, and 3600s, which correspond to the last minute, the last ten minutes, and the last hour till now.

Obtain the Corresponding Metrics via HTTP Interface¶

Here are some examples:

meta_heartbeat_qps.avg.60         // the average QPS of the heart beat in the last minute
meta_heartbeat_error_qps.count.60   // the total errors occurred of the heart beat in the last minute
meta_heartbeat_latency.avg.60     // the average latency of the heart beat in the last minute

Assume that a Nebula Graph meta service is started locally, and the ws_http_port port number is set to 11000 when starting. It is sent through the GET interface of HTTP. The method name is get_stats, and the parameter is stats plus the corresponding metrics name. Here's an example of getting metrics via the HTTP interface:

# obtain a metrics
curl -G "http://127.0.0.1:11000/get_stats?stats=meta_heartbeat_qps.avg.60"
# meta_heartbeat_qps.avg.60=580

# obtain multiple metrics at the same time
curl -G "http://127.0.0.1:11000/get_stats?stats=meta_heartbeat_qps.avg.60,meta_heartbeat_error_qps.avg.60"
# meta_heartbeat_qps.avg.60=537
# meta_heartbeat_error_qps.avg.60=579

# obtain multiple metrics at the same time and return in json format
curl -G "http://127.0.0.1:11000/get_stats?stats=meta_heartbeat_qps.avg.60,meta_heartbeat_error_qps.avg.60&returnjson"
# [{"value":533,"name":"meta_heartbeat_qps.avg.60"},{"value":574,"name":"meta_heartbeat_error_qps.avg.60"}]

# obtain all the metrics
curl -G "http://127.0.0.1:11000/get_stats?stats"
# or
curl -G "http://127.0.0.1:11000/get_stats"