Tuning Process

Locate the real problems, analyze performance bottlenecks, and select the most appropriate tuning method.

Identify problems, find performance bottlenecks, and determine a tuning method based on the bottleneck level.

Figure 1 illustrates the tuning process.

The tuning analysis process is as follows:

1. In most cases, even before the entire pressure test traffic enters the server, the pressure test result may fail to meet the expectation due to network factors, such as the bandwidth, maximum number of connections, and limit on the number of new connections.
2. Check whether the key metrics meet the requirements. If not, locate the cause. Generally, you can locate the cause on servers (in most cases) or clients (in a few cases).
3. If the problem cause is on a server, check the hardware metrics such as the CPU, memory, drive I/O, and network I/O metrics. If any abnormal hardware metric is detected, further analysis is required.
4. If the hardware metrics are normal, check the database metrics, such as the wait events and memory hit ratio.
5. If hardware and database metrics are normal, check the algorithms, buffer, cache, synchronization, and asynchronization. If any abnormal metric is detected, further analysis is required.

   Bottleneck	Description
   Hardware/Specifications	Check the CPU, memory, and drive I/O metrics for hardware bottlenecks and network bottlenecks (network bottlenecks can be ignored in a LAN).
   OS	Check for problems related to the operating system, such as Windows, UNIX, or Linux. For example, insufficient physical memory or improper virtual memory settings may cause a sharp decrease of the virtual memory swap efficiency and an increase of response time.
   Database	Check the database configurations. For example, improper parameter settings may cause a slow database processing speed.