FreeBSD 9.1 excessive memory allocations [SOLVED]

Ben Morrow ben at
Thu Mar 28 06:52:08 UTC 2013

Quoth Unga <unga888 at>:
> > I think you may be reading too much into the malloc manpage.  When it
> > mentions the use of per-thread small-object caches to avoid locking it's
> > talking about performance, not thread safety.  Allocations of all sizes
> > are thread-safe, the library just assumes that huge allocations are rare
> > enough that it doesn't use extra per-thread resources to avoid locking
> > for them, it just uses locking for huge blocks.
> Good to note all allocations are thread safe in FreeBSD. Is it by some
> standard that malloc should be thread safe regardless the OS (BSDs,
> Linux, Windows, Android, etc)?

POSIX (well, SUSv4 at least) says that malloc and free must be
threadsafe. Note that Windows is not a POSIX system, though I belive
malloc is also always threadsafe on Windows.


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