On Wed, Feb 22, 2012 at 05:13:04PM +0100, Jiri Kosina wrote: > Behavior of THP can either be toggled through sysfs in runtime or using a > kernel cmdline parameter 'transparent_hugepage='. Document the latter. > > Signed-off-by: Jiri Kosina <jkosina@xxxxxxx> > --- > Documentation/kernel-parameters.txt | 7 +++++++ > Documentation/vm/transhuge.txt | 3 +++ > 2 files changed, 10 insertions(+), 0 deletions(-) > > diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt > index 033d4e6..a4de9b9 100644 > --- a/Documentation/kernel-parameters.txt > +++ b/Documentation/kernel-parameters.txt > @@ -2629,6 +2629,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted. > to facilitate early boot debugging. > See also Documentation/trace/events.txt > > + transparent_hugepage= > + [KNL] > + Format: [always|madvise|never] > + Can be used to control the default behavior of the system > + with respect to transparent hugepages. > + See Documentation/vm/transhuge.txt for more details. > + > tsc= Disable clocksource stability checks for TSC. > Format: <string> > [x86] reliable: mark tsc clocksource as reliable, this Ok. > diff --git a/Documentation/vm/transhuge.txt b/Documentation/vm/transhuge.txt > index 29bdf62..4a3816d 100644 > --- a/Documentation/vm/transhuge.txt > +++ b/Documentation/vm/transhuge.txt > @@ -103,6 +103,9 @@ echo always >/sys/kernel/mm/transparent_hugepage/enabled > echo madvise >/sys/kernel/mm/transparent_hugepage/enabled > echo never >/sys/kernel/mm/transparent_hugepage/enabled > > +The always/madvise/never value can also be specified on the kernel boot > +commandline using 'transparent_hugepage=' parameter. > + > It's also possible to limit defrag efforts in the VM to generate This is a dup. == Boot parameter == You can change the sysfs boot time defaults of Transparent Hugepage Support by passing the parameter "transparent_hugepage=always" or "transparent_hugepage=madvise" or "transparent_hugepage=never" (without "") to the kernel command line. > hugepages in case they're not immediately free to madvise regions or > to never try to defrag memory and simply fallback to regular pages > -- > 1.7.3.1 > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>