# Metrics¶

This topic will describe the monitoring metrics in Nebula Dashboard.

Note

The default unit in Disk and Network is byte. The unit will be changed with the data magnitude as the page displays. For example, when the flow is less than 1 KB/s, the unit will be Bytes/s.

## Machine¶

### CPU¶

Parameter Description
cpu_utilization The percentage of used CPU.
cpu_idle The percentage of idled CPU.
cpu_wait The percentage of CPU waiting for IO operations.
cpu_user The percentage of CPU used by users.
cpu_system The percentage of CPU used by the system.

### Memory¶

Parameter Description
memory_utilization The percentage of used memory.
memory_used The memory space used (including caches).
memory_actual_used The memory space used (not including caches).
memory_free The memory space available.

Parameter Description
load_1m The average load of the system in the last 1 minute.
load_5m The average load of the system in the last 5 minutes.
load_15m The average load of the system in the last 15 minutes.

### Disk¶

Parameter Description
disk_used The disk space used.
disk_free The disk space available.
disk_readbytes The number of bytes that the system reads in the disk per second.
disk_writebytes The number of bytes that the system writes in the disk per second.
disk_readiops The number of read queries that the disk receives per second.
disk_writeiops The number of write queries that the disk receives per second.
inode_utilization The percentage of used inode.

### Network¶

Parameter Description
network_in_rate The number of bytes that the network card receives per second.
network_out_rate The number of bytes that the network card sends out per second.
network_in_errs The number of wrong bytes that the network card receives per second.
network_out_errs The number of wrong bytes that the network card sends out per second.
network_in_packets The number of data packages that the network card receives per second.
network_out_packets The number of data packages that the network card sends out per second.

## Service¶

### Period¶

The period is the time range of counting metrics. It currently supports 5 seconds, 60 seconds, 600 seconds, and 3600 seconds, which respectively represent the last 5 seconds, the last 1 minute, the last 10 minutes, and the last 1 hour.

### Metric methods¶

Parameter Description
rate The average rate of operations per second in a period.
sum The sum of operations in the period.
avg The average latency in the cycle.
P75 The 75th percentile latency.
P95 The 95th percentile latency.
P99 The 99th percentile latency.
P999 The 99.9th percentile latency.

### Graph¶

Parameter Description
num_queries The number of queries.
num_slow_queries The number of slow queries.
query_latency_us The average latency of queries.
slow_query_latency_us The average latency of slow queries.
num_query_errors The number of queries in error.

### Meta¶

Parameter Description
heartbeat_latency_us The latency of heartbeats.
num_heartbeats The number of heartbeats.

### Storage¶

Parameter Description
add_edges_latency_us The average latency of adding edges.
add_vertices_latency_us The average latency of adding vertices.
delete_edges_latency_us The average latency of deleting edges.
delete_vertices_latency_us The average latency of deleting vertices.
get_neighbors_latency_us The average latency of querying neighbors.

Last update: November 9, 2021