Date: Wed, 29 Nov 2006 11:14:41 +0100 From: "Beat Gaetzi" <beat@chruetertee.ch> To: FreeBSD-gnats-submit@FreeBSD.org Subject: docs/105997: sys/kern/sys_pipe.c refer to tuning(7), but there is no information about kern.ipc.maxpipekva in tuning(7) Message-ID: <4513C85201013ACD@mail16.bluewin.ch> (added by postmaster@bluewin.ch) Resent-Message-ID: <200611291020.kATAKCKJ009988@freefall.freebsd.org>
next in thread | raw e-mail | index | archive | help
>Number: 105997
>Category: docs
>Synopsis: sys/kern/sys_pipe.c refer to tuning(7), but there is no information about kern.ipc.maxpipekva in tuning(7)
>Confidential: no
>Severity: non-critical
>Priority: low
>Responsible: freebsd-doc
>State: open
>Quarter:
>Keywords:
>Date-Required:
>Class: doc-bug
>Submitter-Id: current-users
>Arrival-Date: Wed Nov 29 10:20:12 GMT 2006
>Closed-Date:
>Last-Modified:
>Originator: Beat Gätzi
>Release: FreeBSD 6.2-RC1 i386
>Organization:
>Environment:
System: FreeBSD daedalus.network.local 6.2-RC1 FreeBSD 6.2-RC1 #0: Sun Nov 19 19:23:21 CET 2006 beat@daedalus.network.local:/usr/obj/usr/src/sys/BEASTIE i386
>Description:
In sys/kern/sys_pipe.c there is a refer to tuning(7):
printf("kern.ipc.maxpipekva exceeded; see tuning(7)\n");
But in share/man/man7/tuning.7 there is no information about this sysctl MIB.
>How-To-Repeat:
>Fix:
- Remove reference to tuning(7) from sys_pipe.c
or
- Add a paragraph about kern.ipc.maxpipekva to tuning.7. I found some information
about this sysctl MIB in the comments of sys_pipe.c, but I'm not sure if this is
usefull:
* kern.ipc.maxpipekva - This is a hard limit on the amount of pageable
* address space available to us in pipe_map. This value is normally
* autotuned, but may also be loader tuned.
*
* kern.ipc.pipekva - This read-only sysctl tracks the current amount of
* memory in use by pipes.
*
* Based on how large pipekva is relative to maxpipekva, the following
* will happen:
*
* 0% - 50%:
* New pipes are given 16K of memory backing, pipes may dynamically
* grow to as large as 64K where needed.
* 50% - 75%:
* New pipes are given 4K (or PAGE_SIZE) of memory backing,
* existing pipes may NOT grow.
* 75% - 100%:
* New pipes are given 4K (or PAGE_SIZE) of memory backing,
* existing pipes will be shrunk down to 4K whenever possible.
>Release-Note:
>Audit-Trail:
>Unformatted:
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?4513C85201013ACD>