linux/Documentation/sysctl, branch v2.6.29.3

Update of Documentation: vm.txt and proc.txt

2009-01-16T00:39:35Z

Update Documentation/sysctl/vm.txt and Documentation/filesystems/proc.txt. More specifically, the section on /proc/sys/vm in Documentation/filesystems/proc.txt was removed and a link to Documentation/sysctl/vm.txt added. Most of the verbiage from proc.txt was simply moved in vm.txt, with new addtional text for "swappiness" and "stat_interval". Signed-off-by: Peter W Morreale Acked-by: Randy Dunlap Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

NOMMU: Make mmap allocation page trimming behaviour configurable.

2009-01-08T12:04:47Z

NOMMU mmap allocates a piece of memory for an mmap that's rounded up in size to the nearest power-of-2 number of pages. Currently it then discards the excess pages back to the page allocator, making that memory available for use by other things. This can, however, cause greater amount of fragmentation. To counter this, a sysctl is added in order to fine-tune the trimming behaviour. The default behaviour remains to trim pages aggressively, while this can either be disabled completely or set to a higher page-granular watermark in order to have finer-grained control. vm region vm_top bits taken from an earlier patch by David Howells. Signed-off-by: Paul Mundt Signed-off-by: David Howells Tested-by: Mike Frysinger

mm: add dirty_background_bytes and dirty_bytes sysctls

2009-01-06T23:59:03Z

This change introduces two new sysctls to /proc/sys/vm: dirty_background_bytes and dirty_bytes. dirty_background_bytes is the counterpart to dirty_background_ratio and dirty_bytes is the counterpart to dirty_ratio. With growing memory capacities of individual machines, it's no longer sufficient to specify dirty thresholds as a percentage of the amount of dirtyable memory over the entire system. dirty_background_bytes and dirty_bytes specify quantities of memory, in bytes, that represent the dirty limits for the entire system. If either of these values is set, its value represents the amount of dirty memory that is needed to commence either background or direct writeback. When a `bytes' or `ratio' file is written, its counterpart becomes a function of the written value. For example, if dirty_bytes is written to be 8096, 8K of memory is required to commence direct writeback. dirty_ratio is then functionally equivalent to 8K / the amount of dirtyable memory: dirtyable_memory = free pages + mapped pages + file cache dirty_background_bytes = dirty_background_ratio * dirtyable_memory -or- dirty_background_ratio = dirty_background_bytes / dirtyable_memory AND dirty_bytes = dirty_ratio * dirtyable_memory -or- dirty_ratio = dirty_bytes / dirtyable_memory Only one of dirty_background_bytes and dirty_background_ratio may be specified at a time, and only one of dirty_bytes and dirty_ratio may be specified. When one sysctl is written, the other appears as 0 when read. The `bytes' files operate on a page size granularity since dirty limits are compared with ZVC values, which are in page units. Prior to this change, the minimum dirty_ratio was 5 as implemented by get_dirty_limits() although /proc/sys/vm/dirty_ratio would show any user written value between 0 and 100. This restriction is maintained, but dirty_bytes has a lower limit of only one page. Also prior to this change, the dirty_background_ratio could not equal or exceed dirty_ratio. This restriction is maintained in addition to restricting dirty_background_bytes. If either background threshold equals or exceeds that of the dirty threshold, it is implicitly set to half the dirty threshold. Acked-by: Peter Zijlstra Cc: Dave Chinner Cc: Christoph Lameter Signed-off-by: David Rientjes Cc: Andrea Righi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Document kernel taint flags properly

2008-10-29T22:03:49Z

This fills in the documentation for all of the current kernel taint flags, and fixes the number for TAINT_CRAP, which was incorrectly described. Cc: Michael Kerrisk Cc: Randy Dunlap Signed-off-by: Greg Kroah-Hartman

Staging: add TAINT_CRAP for all drivers/staging code

2008-10-10T22:31:05Z

We need to add a flag for all code that is in the drivers/staging/ directory to prevent all other kernel developers from worrying about issues here, and to notify users that the drivers might not be as good as they are normally used to. Based on code from Andreas Gruenbacher and Jeff Mahoney to provide a TAINT flag for the support level of a kernel module in the Novell enterprise kernel release. This is the kernel portion of this feature, the ability for the flag to be set needs to be done in the build process and will happen in a follow-up patch. Cc: Andreas Gruenbacher Cc: Jeff Mahoney Signed-off-by: Greg Kroah-Hartman

Documentation/sysctl/kernel.txt: fix softlockup_thresh description

2008-09-23T15:09:14Z

- s/s/seconds/ - s/10 seconds/60 seconds/ - Mention the zero-disables-it feature. Cc: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Documentation cleanup: trivial misspelling, punctuation, and grammar corrections.

2008-07-26T19:00:06Z

Cc: Randy Dunlap Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Documentation: sysctl/kernel.txt: fix documentation reference

2008-02-14T00:21:20Z

This patch fixes a reference to Documentation/kmod.txt which was apparently renamed to Documentation/debugging-modules.txt Signed-off-by: Michael Opdenacker Cc: "Randy.Dunlap" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

brk: document randomize_va_space and CONFIG_COMPAT_BRK (was Re:

2008-02-09T22:24:08Z

Document randomize_va_space and CONFIG_COMPAT_BRK. Signed-off-by: Jiri Kosina Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner

oom: add sysctl to enable task memory dump

2008-02-07T16:42:19Z

Adds a new sysctl, 'oom_dump_tasks', that enables the kernel to produce a dump of all system tasks (excluding kernel threads) when performing an OOM-killing. Information includes pid, uid, tgid, vm size, rss, cpu, oom_adj score, and name. This is helpful for determining why there was an OOM condition and which rogue task caused it. It is configurable so that large systems, such as those with several thousand tasks, do not incur a performance penalty associated with dumping data they may not desire. If an OOM was triggered as a result of a memory controller, the tasklist shall be filtered to exclude tasks that are not a member of the same cgroup. Cc: Andrea Arcangeli Cc: Christoph Lameter Cc: Balbir Singh Signed-off-by: David Rientjes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds