PostgreSQL monitoring metrics (such as query latency, throughput, memory usage, etc.) #

What are Monitoring Metrics?

Monitoring metrics are key parameters used to evaluate system performance and stability, including query latency, throughput, memory usage rate, network transfer speed, etc. These metrics help us understand the load on the system and allow for adjustments as needed.

Query Latency (Query Latency)

Query latency refers to the time required from when a request is received by the database until results are returned. It is typically influenced by the following factors:

• A slower network connection
• A database that cannot handle requests
• The situation where most requests are issued at the same time
• Some high-resource-consuming background jobs causing delays

Throughput (Throughput)

Throughput refers to the number of requests a system can process within a unit of time. It is an important metric for measuring system performance.

Factors affecting PostgreSQL throughput:

• CPU: A stronger CPU will result in better throughput.
• Disk I/O: Disk I/O is a major bottleneck caused by the CPU's downward pressure. Using SSDs can significantly improve throughput.

Memory Usage Rate (Memory Usage)

The memory usage rate refers to the proportion of available memory within the system's total memory. High memory usage rates may lead to decreased system performance.

Factors affecting memory usage:

• Database size: Larger databases require more memory.
• Number and size of tables and indexes: Larger tables or indexes consume more memory.
• Number and size of transactions

Network Transfer Speed (Network Transfer Speed)

Network transfer speed refers to the amount of data sent over a network within a unit of time.

Factors affecting network transfer speed:

• Quality of network connection: A slower network connection leads to greater latency and lower throughput.
• Database size, number and size of tables: Larger databases require more data to be transferred.