K 10
svn:author
V 7
rwatson
K 8
svn:date
V 27
2005-07-23T17:11:33.000000Z
K 7
svn:log
V 2063
Merge kern_malloc.c:1.143,1.144 malloc.h:1.81 from HEAD to RELENG_6:

  Introduce a new sysctl, kern.malloc_stats, which exports kernel malloc
  statistics via a binary structure stream:

  - Add structure 'malloc_type_stream_header', which defines a stream
    version, definition of MAXCPUS used in the stream, and a number of
    malloc_type records in the stream.

  - Add structure 'malloc_type_header', which defines the name of the
    malloc type being reported on.

  - When the sysctl is queried, return a stream header, followed by a
    series of type descriptions, each consisting of a type header
    followed by a series of MAXCPUS malloc_type_stats structures holding
    per-CPU allocation information.  Typical values of MAXCPUS will be 1
    (UP compiled kernel) and 16 (SMP compiled kernel).

  This query mechanism allows user space monitoring tools to extract
  memory allocation statistics in a machine-readable form, and to do so
  at a per-CPU granularity, allowing monitoring of allocation patterns
  across CPUs in order to better understand the distribution of work and
  memory flow over multiple CPUs.

  While here:

  - Bump statistics width to uint64_t, and hard code using fixed-width
    type in order to be more sure about structure layout in the stream.
    We allocate and free a lot of memory.

  - Add kmemcount, a counter of the number of registered malloc types,
    in order to avoid excessive manual counting of types.  Export via a
    new sysctl to allow user-space code to better size buffers.

  - De-XXX comment on no longer maintaining the high watermark in old
    sysctl monitoring code.

  A follow-up commit of libmemstat(3), a library to monitor kernel memory
  allocation, will occur in the next few days.  Likewise, similar changes
  to UMA.

kern_malloc.c:1.144:

  Correct build on 64-bit: cast u_int64_t to (unsigned long long) before
  printfing as (unsigned long long).  32-bit build on i386 didn't notice
  this.  Whoops.

  Reported by:    arved
  Tested by:      sledge

Approved by:	re (kensmith)

END