Need the equiv. of SYSINFO data under 4.2

[Chris Torek]

> I need the page buffer statistics bread and lread (buffer reads,
> logical reads) that are available from SV UNIX in the SYSINFO
> structure.

I'm not sure what you mean by ``page buffer statistics'', but all
the per-process resource usage statistics in 4.2BSD are declared
in the files <sys/resource.h>.  The paging statistics are kept in

	long	ru_minflt;		/* page reclaims */
	long	ru_majflt;		/* page faults */
and
	long	ru_nswap;		/* swaps */

The block I/O system statistics are kept in

	long	ru_inblock;		/* block input operations */
	long	ru_oublock;		/* block output operations */

There is no separate field for read-ahead cache hits; processes must
pay for their read-ahead blocks even if they never use them.

The resource usage stuff is obtained through the wait3() system call
(see man 2 wait).

If you are trying to analyze the buffer cache hit ratio, you can use
the (undocumented) vtrace() system call to enable the cache trace points,
if your kernel was compiled with -DTRACE.
-- 
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In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 7690)
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