[c] Faster way to zero memory than with memset?

Nowadays your compiler should do all the work for you. At least of what I know gcc is very efficient in optimizing calls to memset away (better check the assembler, though).

Then also, avoid memset if you don't have to:

  • use calloc for heap memory
  • use proper initialization (... = { 0 }) for stack memory

And for really large chunks use mmap if you have it. This just gets zero initialized memory from the system "for free".