docs/73429: [patch] Update Handbook, Chapter 8, kernel configuration

Joel Dahl joel at automatvapen.se
Tue Nov 2 18:40:29 UTC 2004


>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 at 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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