linux/Documentation/sysctl, branch v2.6.18

[PATCH] Fix docs for fs.suid_dumpable

2006-08-27T18:01:28Z

Sergey Vlasov noticed that there is not kernel.suid_dumpable, but fs.suid_dumpable. How KERN_SETUID_DUMPABLE ended up in fs_table[]? Hell knows... Signed-off-by: Alexey Dobriyan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] doc: update panic_on_oops documentation

2006-08-06T15:57:47Z

Signed-off-by: Maxime Bizon Acked-by: Simon Horman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] ZVC/zone_reclaim: Leave 1% of unmapped pagecache pages for file I/O

2006-07-03T22:26:59Z

It turns out that it is advantageous to leave a small portion of unmapped file backed pages if all of a zone's pages (or almost all pages) are allocated and so the page allocator has to go off-node. This allows recently used file I/O buffers to stay on the node and reduces the times that zone reclaim is invoked if file I/O occurs when we run out of memory in a zone. The problem is that zone reclaim runs too frequently when the page cache is used for file I/O (read write and therefore unmapped pages!) alone and we have almost all pages of the zone allocated. Zone reclaim may remove 32 unmapped pages. File I/O will use these pages for the next read/write requests and the unmapped pages increase. After the zone has filled up again zone reclaim will remove it again after only 32 pages. This cycle is too inefficient and there are potentially too many zone reclaim cycles. With the 1% boundary we may still remove all unmapped pages for file I/O in zone reclaim pass. However. it will take a large number of read and writes to get back to 1% again where we trigger zone reclaim again. The zone reclaim 2.6.16/17 does not show this behavior because we have a 30 second timeout. [akpm@osdl.org: rename the /proc file and the variable] Signed-off-by: Christoph Lameter Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] zoned vm counters: zone_reclaim: remove /proc/sys/vm/zone_reclaim_interval

2006-06-30T18:25:35Z

The zone_reclaim_interval was necessary because we were not able to determine how many unmapped pages exist in a zone. Therefore we had to scan in intervals to figure out if any pages were unmapped. With the zoned counters and NR_ANON_PAGES we now know the number of pagecache pages and the number of mapped pages in a zone. So we can simply skip the reclaim if there is an insufficient number of unmapped pages. We use SWAP_CLUSTER_MAX as the boundary. Drop all support for /proc/sys/vm/zone_reclaim_interval. Signed-off-by: Christoph Lameter Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] support for panic at OOM

2006-06-23T14:42:47Z

This patch adds panic_on_oom sysctl under sys.vm. When sysctl vm.panic_on_oom = 1, the kernel panics intead of killing rogue processes. And if vm.panic_on_oom is 0 the kernel will do oom_kill() in the same way as it does today. Of course, the default value is 0 and only root can modifies it. In general, oom_killer works well and kill rogue processes. So the whole system can survive. But there are environments where panic is preferable rather than kill some processes. Signed-off-by: KAMEZAWA Hiroyuki Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] suspend-to-ram: allow video options to be set at runtime

2006-02-21T04:00:10Z

Currently, acpi video options can only be set on kernel command line. That's little inflexible; I'd like userland s2ram application that just works, and modifying kernel command line according to whitelist is not fun. It is better to just allow s2ram application to set video options just before suspend (according to the whitelist). This implements sysctl to allow setting suspend video options without reboot. (akpm: Documentation updates for this new sysctl are pending..) Signed-off-by: Pavel Machek Cc: "Brown, Len" Cc: "Antonino A. Daplas" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] Reclaim slab during zone reclaim

2006-02-01T16:53:16Z

If large amounts of zone memory are used by empty slabs then zone_reclaim becomes uneffective. This patch shakes the slab a bit. The problem with this patch is that the slab reclaim is not containable to a zone. Thus slab reclaim may affect the whole system and be extremely slow. This also means that we cannot determine how many pages were freed in this zone. Thus we need to go off node for at least one allocation. The functionality is disabled by default. We could modify the shrinkers to take a zone parameter but that would be quite invasive. Better ideas are welcome. Signed-off-by: Christoph Lameter Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] Zone reclaim: Allow modification of zone reclaim behavior

2006-02-01T16:53:16Z

In some situations one may want zone_reclaim to behave differently. For example a process writing large amounts of memory will spew unto other nodes to cache the writes if many pages in a zone become dirty. This may impact the performance of processes running on other nodes. Allowing writes during reclaim puts a stop to that behavior and throttles the process by restricting the pages to the local zone. Similarly one may want to contain processes to local memory by enabling regular swap behavior during zone_reclaim. Off node memory allocation can then be controlled through memory policies and cpusets. Signed-off-by: Christoph Lameter Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] zone_reclaim: configurable off node allocation period.

2006-02-01T16:53:16Z

Currently the zone_reclaim code has a fixed window of 30 seconds of off node allocations should a local zone have no unused pagecache pages left. Reclaim will be attempted again after this timeout period to avoid repeated useless scans for memory. This is also useful to established sufficiently large off node allocation chunks to relieve the local node. It may be beneficial to adjust that time period for some special situations. For example if memory use was exceeding node capacity one may want to give up for longer periods of time. If memory spikes intermittendly then one may want to shorten the time period to reduce the number of off node allocations. This patch allows just that.... Signed-off-by: Christoph Lameter Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] Zone reclaim: proc override

2006-01-19T03:20:17Z

proc support for zone reclaim This patch creates a proc entry /proc/sys/vm/zone_reclaim_mode that may be used to override the automatic determination of the zone reclaim made on bootup. Signed-off-by: Christoph Lameter Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds