Memory Allocation/Deallocation Bottleneck?

Question

How much of a bottleneck is memory allocation/deallocation in typical real-world programs? Answers from any type of program where performance typically matters are welcome.

Answer 1

In Java (and potentially other languages with a decent GC implementation) allocating an object is very cheap. In the SUN JVM it only needs 10 CPU Cycles. A malloc in C/c++ is much more expensive, just because it has to do more work.

Still even allocation objects in Java is very cheap, doing so for a lot of users of a web application in parallel can still lead to performance problems, because more Garbage Collector runs will be triggered. Therefore there are those indirect costs of an allocation in Java caused by the deallocation done by the GC. These costs are difficult to quantify because they depend very much on your setup (how much memory do you have) and your application.