Do Try/Catch Blocks Significantly Impact Performance When No Exceptions Are Thrown?

The impact of try/catch blocks on performance without exceptions

While reviewing code with Microsoft employees, a question arose regarding the potential performance impact of large numbers of try/catch blocks. The employee suggested limiting try/catch blocks to critical sections of code to avoid overuse.

How do try/catch blocks affect performance?

Although try/catch blocks provide a powerful error handling mechanism, they may introduce performance overhead if executed frequently. When an exception is thrown, the try/catch block is activated and the JVM performs additional operations to handle the exception and resume execution state. However, this overhead only occurs when an exception occurs.

Performance Impact Test

To measure the actual performance impact, a simple benchmark was conducted comparing the execution time of code with and without try/catch blocks. The benchmark consists of repeatedly calculating the sine of a number in a loop. It turns out that the try/catch block incurs an overhead of about 4 milliseconds per million iterations.

Additional test containing finally block

Further testing was conducted to evaluate the performance impact of finally blocks, which are often used together with try/catch blocks. It turns out that finally blocks also incur overhead, but slightly less than try/catch blocks.

Conclusion

In summary, try/catch blocks do introduce a small amount of performance overhead when no exception is thrown. However, for most practical applications this overhead is relatively insignificant. The main factor to consider is the frequency of expected anomalies. If exceptions are likely to occur frequently, the additional overhead may become more apparent.

The above is the detailed content of Do Try/Catch Blocks Significantly Impact Performance When No Exceptions Are Thrown?. For more information, please follow other related articles on the PHP Chinese website!