What is a safe Maximum Stack Size or How to measure use of stack?

Question

I have an app with a number of worker threads, one for each core. On a modern 8 core machine, I have 8 of these threads. My app loads a lot of plugins, which also have their

Answer 1

Whilst I am sure that you can reduce the thread stacksize in your app, I don't think it will address the root cause of the problem. You are using an 8 core machine now, but what happens on a 16 core, or a 32 core etc.

With 32 bit Delphi you have a maximum address space of 4GB and so this does limit you to some degree. You may well need to use smaller stacks for some or all of your threads, but you will still face problems on a big enough machine.

If you help your app scale better to larger machines you may need to take one or other of the following steps:

1. Avoid creating significantly more threads than cores. Use a thread pool architecture that is available to your plug-ins. Without the benefit of the .net environment to make this easy you will be best coding against the Windows thread pool API. That said, there must be a good Delphi wrapper available.
2. Deal with the memory allocation patterns. If your threads are allocating contiguous blocks in the region of 200MB then this is going to cause undue stress on your allocator. I have found that it is often best to allocate such large amounts of memory in smaller, fixed size blocks. This approach works around the fragmentation problems you are encountering.