Truy vấn (PromQL)
- Is the system running?
- HTTP status codes rate
- Average response time
- Slowest 5 requests (average)
- More called endpoints
- CPU used per minute group by instance
- Request total per minute by instance
- Used memory (MB)
- Free memory (percentage 0-100)
Tổng quan
Prometheus hỗ trợ ngôn ngữ PromQL để thực hiện truy vấn với Prometheus. Các truy vấn có thể dùng để tạo các biểu thức cho record rule hoặc có thể chỉ là các truy vấn ad-hoc trên WebUI của Prometheus để phân tích thông tin monitor. Xem chi tiết về truy vấn PromQL
Giao diện web query
Q001
Is the system running?
up{instance="<instance_tag>"}
Q002
HTTP status codes rate
sum(http_server_requests_total{code=~"4..", instance="<instance_tag>"}) / sum(http_server_requests_total{instance="<instance_tag>"})
Note: 4.. in the code pattern can be replaced with different numbers.
Q003
Average response time
sum(http_server_request_duration_seconds_sum) / sum(http_server_request_duration_seconds_count) * 1000
Q004
Slowest 5 requests (average)
topk(5, http_server_request_duration_seconds_sum / http_server_request_duration_seconds_count * 1000)
Q005
More called endpoints
topk(10, http_request_total or http_requests_total or http_server_requests_total)
Q006
CPU used per minute group by instance
sum(rate(process_cpu_seconds_total{}[1m])) by (instance)
Q007
Request total per minute by instance
sum(rate(http_requests_total[1m])) by (instance)
Q008
Used memory (MB)
(node_memory_bytes_total - node_memory_free_bytes_total) / 1024 /1024
Q009
Free memory (percentage 0-100)
node_memory_free_bytes_total / node_memory_bytes_total * 100.0