I don't understand the difference between MEM_RELEASE and MEM_DECOMMIT in the Windows VirtualFree function.
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MEM_RELEASE will free the mapping completely like munmap on Linux, making the address space usable for other things.
MEM_DECOMMIT will release the memory but hold onto the reserve address space like clobbering a mapping with mmap + MAP_FIXED + PROT_NONE on Linux.
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What does "hold onto" mean in this context? Does it mean the process continues to reserve the memory but the content pages are discarded?
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Or does it mean the process continues to reserve the memory AND the pointer but the content is invalidated?
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MEM_DECOMMIT is the same as making a fresh mapping with VirtualAlloc using MEM_RESERVE.
You go from a reserved mapping to usable memory with MEM_COMMIT like using mprotect for that purpose on Linux. Windows separates the concept of whether it's committed from protection mode.
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