svn commit: r258495 - head/release/doc/en_US.ISO8859-1/hardware

[Alexander Motin]

Author: mav
Date: Sat Nov 23 11:46:13 2013
New Revision: 258495
URL: http://svnweb.freebsd.org/changeset/base/258495

Log:
  MFreleng/8.4 r251256 (by hrs):
  Update description of logical CPU handling in the latest releases and
  remove obsolete sysctl variable machdep.hlt_logical_cpus.
  
  MFC after:	3 days

Modified:
  head/release/doc/en_US.ISO8859-1/hardware/article.xml

Modified: head/release/doc/en_US.ISO8859-1/hardware/article.xml
==============================================================================
--- head/release/doc/en_US.ISO8859-1/hardware/article.xml	Sat Nov 23 03:56:03 2013	(r258494)
+++ head/release/doc/en_US.ISO8859-1/hardware/article.xml	Sat Nov 23 11:46:13 2013	(r258495)
@@ -177,16 +177,13 @@
 	bugs may generate some problems.  Perusal of the archives of
 	the &a.smp; may yield some clues.</para>
 
-      <para>&os; will take advantage of HyperThreading (HTT) support
-	on &intel; CPUs that support this feature.  The
-	default &os; scheduler treats the logical processors the same
-	as additional physical processors; in other words, no attempt
-	is made to optimize scheduling decisions given the shared
-	resources between logical processors within the same CPU.
-	Because this naive scheduling can result in suboptimal
-	performance, under certain circumstances it may be useful to
-	disable the logical processors with the
-	<varname>machdep.hyperthreading_allowed</varname> tunable.
+      <para>&os; will take advantage of SMT (Symmetric MultiThreading,
+	also known as HyperThreading on &intel; CPUs) on the supported
+	CPUs.  The <filename>GENERIC</filename> kernel which is
+	installed by default will automatically detect the additional
+	logical processors.  The default &os; scheduler recognizes
+	processor topology on the system and selects logical and
+	physical processors to obtain optimal performance.
 	The &man.smp.4; manual page has more details.</para>
 
       <para>&os; will take advantage of Physical Address Extensions