Date: Tue, 2 Nov 2004 19:32:47 +0100 From: "Joel Dahl" <joel@automatvapen.se> To: FreeBSD-gnats-submit@FreeBSD.org Subject: docs/73429: [patch] Update Handbook, Chapter 8, kernel configuration Message-ID: <20041102183220.53DCE37E7B@smtp4-2-sn2.hy.skanova.net> Resent-Message-ID: <200411021840.iA2IeTlr044467@freefall.freebsd.org>
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>Number: 73429
>Category: docs
>Synopsis: [patch] Update Handbook, Chapter 8, kernel configuration
>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: Tue Nov 02 18:40:29 GMT 2004
>Closed-Date:
>Last-Modified:
>Originator: Joel Dahl
>Release: FreeBSD 5.2.1-RELEASE-p9 i386
>Organization:
>Environment:
System: FreeBSD dude.automatvapen.se 5.2.1-RELEASE-p9 FreeBSD 5.2.1-RELEASE-p9 #2: Sat Oct 30 14:56:56 CEST 2004 joel@dude.automatvapen.se:/usr/obj/usr/src/sys/WORKSTATION i386
>Description:
[1] Update the weak description of ADAPTIVE_GIANT.
[2] Option SMP was removed from GENERIC in RELENG_5 and RELENG_5_3, so it
should probably be removed here as well.
[3] Update description for apic since SMP is gone.
[4] Device hptmv now ships with RELENG_5 and RELENG_5_3, but it's missing
in here, so let's add it.
See attached patch for suggested corrections.
>How-To-Repeat:
>Fix:
--- kernconf.diff begins here ---
--- chapter.sgml Sun Oct 31 09:06:48 2004
+++ new.chapter.sgml Tue Nov 2 19:04:34 2004
@@ -893,19 +893,26 @@
<programlisting>options ADAPTIVE_GIANT # Giant mutex is adaptive.</programlisting>
- <para>This option causes Giant to be included in the set of mutexes
- adaptively spun on.</para>
+ <para>Giant is the name of a mutual exclusion mechanism (a sleep mutex)
+ that protects a large set of kernel resources. Today, this is an
+ unacceptable performance bottleneck which is actively beeing replaced
+ with locks that protect individual resources. The ADAPTIVE_GIANT
+ option causes Giant to be included in the set of mutexes adaptively
+ spun on. That is, when a thread wants to lock the Giant mutex, but it
+ is already locked by a thread on another CPU, the first thread will
+ keep running and wait for the lock to be released. Normally, the
+ thread would instead go back to sleep and wait for its next chance to
+ run.</para>
<indexterm>
<primary>kernel options</primary>
<secondary>SMP</secondary>
</indexterm>
- <programlisting># To make an SMP kernel, the next two are needed
-options SMP # Symmetric MultiProcessor Kernel
-device apic # I/O APIC</programlisting>
+ <programlisting>device apic # I/O APIC</programlisting>
- <para>The above are both required for SMP support, and can also be
- safely enabled on uniprocessor systems.</para>
+ <para>The apic device enables the use of I/O APIC for interrupt
+ delivery. The apic device can be used in both UP and SMP kernels, but
+ is required for SMP kernels.</para>
<programlisting>device isa</programlisting>
@@ -1026,6 +1033,7 @@
device asr # DPT SmartRAID V, VI and Adaptec SCSI RAID
device ciss # Compaq Smart RAID 5*
device dpt # DPT Smartcache III, IV - See NOTES for options
+device hptmv # Highpoint RocketRAID 182x
device iir # Intel Integrated RAID
device ips # IBM (Adaptec) ServeRAID
device mly # Mylex AcceleRAID/eXtremeRAID
--- kernconf.diff ends here ---
>Release-Note:
>Audit-Trail:
>Unformatted:
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