PrefaceThis article continues to explain how to tune the concepts that are relevant to performance optimization in the previous chapter. Code optimization is the most common of us, but there are also software architectures, JVM virtual machine tiers, databases, and operating system levels that can be tuned in various ways to improve performance.
The
Chase
General steps for optimization:If there is a problem with our system, then the most important thing is to find and solve the performance bottleneck, while performance optimization may make a big change to the original implementation, so be sure to test hit the target before the end.
1. Design tuning: Design phasea good system design can avoid many potential performance problems. Therefore, taking as much time as possible in system design is the key to creating high-performance programs.
we have learned design patterns, so we need to use design patterns in the design phase, such as single case, agent, enjoy meta, observer pattern and so on. In addition to design patterns, we can use optimized components, such as buffering, caching, connection pooling, and so on, in the design phase, as appropriate for the business.
2. Code tuning: Development PhaseThis is the developer is most familiar with, do the overloading should have feelings, the same function, good implementation and bad implementation is very far. be careful to avoid deadlocks, dead loops.
3. Database tuning: Development phaseJava programs can connect to a database using JDBC, so our team database tuning can be divided into 3 parts:1. Optimizing SQL statements at the application layer2. Optimize the database3. Optimization of database software
4. Operating system tuningDifferent operating system tuning methods and parameters, such as shared memory segments, semaphores, shared memory maximum, shared memory minimum value are can be optimized system resources.
Summary:the next chapter will describe the tuning methods for each stage in detail.
Java Program Performance Optimization-Tuning hierarchy
