How to solve Memory Fragmentation

Question

We\'ve occasionally been getting problems whereby our long-running server processes (running on Windows Server 2003) have thrown an exception due to a memory allocation fail

Answer 1

I think you’ve mistakenly ruled out a memory leak too early. Even a tiny memory leak can cause a severe memory fragmentation.

Assuming your application behaves like the following:
Allocate 10MB
Allocate 1 byte
Free 10MB
(oops, we didn’t free the 1 byte, but who cares about 1 tiny byte)

This seems like a very small leak, you will hardly notice it when monitoring just the total allocated memory size. But this leak eventually will cause your application memory to look like this:
.
.
Free – 10MB
.
.
[Allocated -1 byte]
.
.
Free – 10MB
.
.
[Allocated -1 byte]
.
.
Free – 10MB
.
.

This leak will not be noticed... until you want to allocate 11MB
Assuming your minidumps had full memory info included, I recommend using DebugDiag to spot possible leaks. In the generated memory report, examine carefully the allocation count (not size).