libmemstat(3) - Library for monitoring kernel memory use

I've just committed libmemstat(3), a library to support user space 
applications monitoring kernel memory allocation.  This is intended to be 
the new back-end to several existing tools, including:

   vmstat -m
   vmstat -z
   netstat -mb

However, it's also easy to use to build new tools.  For example, 
memtop(8), which provides a top(1)-like interface for monitoring kernel 
memory allocation.  A highly enlightening set of output to see on a busy 
system.  :-)

I've not yet committed the changes to vmstat, netstat, etc, which will 
follow in the next few days once things settle out from the commits that 
went in to support it.  The older sysctls to support older vmstat/netstat 
will remain in place for some period of time while things settle also.

I've put some sample code for using libmemstat(3) up at the following URL:

     http://www.watson.org/~robert/freebsd/libmemstat/

This includes the above-mentioned memtop(8), and a sample memstat(8). 
Since I'm not an ncurses programmer, I've not attempted to use it.  The 
foundations are there for people who do want to build more spiffy 
monitoring tools though.  This might also provide a useful back-end for an 
SNMP module monitoring kernel memory use.

FYI: the libmemstat(3) API will probably change some in the next few weeks 
based on feedback I receive about how usable or unusable it is.

Thanks,

Robert N M Watson

---------- Forwarded message ----------
Date: Thu, 14 Jul 2005 17:40:02 +0000 (UTC)
From: Robert Watson <rwatson_at_FreeBSD.org>
To: src-committers_at_FreeBSD.org, cvs-src_at_FreeBSD.org, cvs-all_at_FreeBSD.org
Subject: cvs commit: src/lib/libmemstat Makefile libmemstat.3 memstat.c
     memstat.h memstat_all.c memstat_internal.h memstat_malloc.c
     memstat_uma.c

rwatson     2005-07-14 17:40:02 UTC

   FreeBSD src repository

   Added files:
     lib/libmemstat       Makefile libmemstat.3 memstat.c memstat.h
                          memstat_all.c memstat_internal.h
                          memstat_malloc.c memstat_uma.c
   Log:
   Add libmemstat(3), a library for use by debugging and monitoring
   applications in tracking kernel memory statistics.  It provides an
   abstracted interface to uma(9) and malloc(9) statistics, wrapped
   around the recently added binary stream sysctls for the allocators.

   Using this interface, it is easy to build monitoring tools, query
   specific memory types for usage information, etc.  Facilities are
   provided for binding caller-provided data to memory types,
   incremental updates of memory types, and queries that span multiple
   allocators.

   Support for additional allocators is (relatively) easy to add.

   The API for libmemstat(3) will probably change some over time as
   consumers are written, and requirements evolve.  It is written to
   avoid encoding ABIs for data structure layout into consuming
   applications for this reason.

   MFC after:      1 week

   Revision  Changes    Path
   1.1       +23 -0     src/lib/libmemstat/Makefile (new)
   1.1       +238 -0    src/lib/libmemstat/libmemstat.3 (new)
   1.1       +366 -0    src/lib/libmemstat/memstat.c (new)
   1.1       +134 -0    src/lib/libmemstat/memstat.h (new)
   1.1       +47 -0     src/lib/libmemstat/memstat_all.c (new)
   1.1       +124 -0    src/lib/libmemstat/memstat_internal.h (new)
   1.1       +240 -0    src/lib/libmemstat/memstat_malloc.c (new)
   1.1       +230 -0    src/lib/libmemstat/memstat_uma.c (new)