cvs commit: src/lib/libc/stdlib malloc.3 malloc.c

[Jason Evans]

jasone      2007-12-27 23:29:44 UTC

  FreeBSD src repository

  Modified files:
    lib/libc/stdlib      malloc.3 malloc.c 
  Log:
  Add the 'D' and 'M' run time options, and use them to control whether
  memory is acquired from the system via sbrk(2) and/or mmap(2).  By default,
  use sbrk(2) only, in order to support traditional use of resource limits.
  Additionally, when both options are enabled, prefer the data segment to
  anonymous mappings, in order to coexist better with large file mappings
  in applications on 32-bit platforms.  This change has the potential to
  increase memory fragmentation due to the linear nature of the data
  segment, but from a performance perspective this is mitigated by the use
  of madvise(2). [1]
  
  Add the ability to interpret integer prefixes in MALLOC_OPTIONS
  processing.  For example, MALLOC_OPTIONS=lllllllll can now be specified as
  MALLOC_OPTIONS=9l.
  
  Reported by:    [1] rwatson
  Design review:  [1] alc, peter, rwatson
  
  Revision  Changes    Path
  1.75      +57 -24    src/lib/libc/stdlib/malloc.3
  1.155     +436 -292  src/lib/libc/stdlib/malloc.c