package devkit

Memory reporting - GC and OS, optionally malloc

General background:

• VSZ is not very intersting, this is the amount of memory which is mapped to the process address space. It's not really memory use, only the amount of memory the process can access without triggering a segfault.
• RSS is resident set size: this is the real world data. It's tracked by kernel and is the amount of memory currently allocated to this process. Most of the time this is what you want to look at.
• Malloc stats: those are metrics tracked by C malloc (jemalloc, tcmalloc, glibc, etc).
• size is basically like VSZ but from malloc point of view. That is it does not include mmap files for instance.
• used is basically RSS from malloc point of view.
• heap is the sum of all currently malloced values for which free had not been called. So this is what application requested, not including metadata, cache, etc
• Gc stats are one level above and are tracked by ocaml gc. e.g. heap is the total size allocate for ocaml program. See Gc module documentation for more details.