summaryrefslogtreecommitdiffstats
path: root/Documentation/sysctl
Commit message (Collapse)AuthorAgeFilesLines
* Staging: add TAINT_CRAP for all drivers/staging codeGreg Kroah-Hartman2008-10-101-0/+1
| | | | | | | | | | | | | | | | | | | | 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 <agruen@suse.de> Cc: Jeff Mahoney <jeffm@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Documentation/sysctl/kernel.txt: fix softlockup_thresh descriptionAndrew Morton2008-09-231-3/+4
| | | | | | | | | | | | - s/s/seconds/ - s/10 seconds/60 seconds/ - Mention the zero-disables-it feature. Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Documentation cleanup: trivial misspelling, punctuation, and grammar ↵Matt LaPlante2008-07-261-1/+1
| | | | | | | | corrections. Cc: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Documentation: sysctl/kernel.txt: fix documentation referenceMichael Opdenacker2008-02-131-1/+1
| | | | | | | | | | This patch fixes a reference to Documentation/kmod.txt which was apparently renamed to Documentation/debugging-modules.txt Signed-off-by: Michael Opdenacker <michael@free-electrons.com> Cc: "Randy.Dunlap" <rdunlap@xenotime.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* brk: document randomize_va_space and CONFIG_COMPAT_BRK (was Re:Jiri Kosina2008-02-091-0/+29
| | | | | | | | Document randomize_va_space and CONFIG_COMPAT_BRK. Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* oom: add sysctl to enable task memory dumpDavid Rientjes2008-02-071-0/+22
| | | | | | | | | | | | | | | | | | | | | | | | | 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 <andrea@suse.de> Cc: Christoph Lameter <clameter@sgi.com> Cc: Balbir Singh <balbir@linux.vnet.ibm.com> Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* get rid of NR_OPEN and introduce a sysctl_nr_openEric Dumazet2008-02-061-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | NR_OPEN (historically set to 1024*1024) actually forbids processes to open more than 1024*1024 handles. Unfortunatly some production servers hit the not so 'ridiculously high value' of 1024*1024 file descriptors per process. Changing NR_OPEN is not considered safe because of vmalloc space potential exhaust. This patch introduces a new sysctl (/proc/sys/fs/nr_open) wich defaults to 1024*1024, so that admins can decide to change this limit if their workload needs it. [akpm@linux-foundation.org: export it for sparc64] Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: "David S. Miller" <davem@davemloft.net> Cc: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/page-writeback: highmem_is_dirtyable optionBron Gondwana2008-02-051-3/+4
| | | | | | | | | | | | | | | | | | | | | Add vm.highmem_is_dirtyable toggle A 32 bit machine with HIGHMEM64 enabled running DCC has an MMAPed file of approximately 2Gb size which contains a hash format that is written randomly by the dbclean process. On 2.6.16 this process took a few minutes. With lowmem only accounting of dirty ratios, this takes about 12 hours of 100% disk IO, all random writes. Include a toggle in /proc/sys/vm/highmem_is_dirtyable which can be set to 1 to add the highmem back to the total available memory count. [akpm@linux-foundation.org: Fix the CONFIG_DETECT_SOFTLOCKUP=y build] Signed-off-by: Bron Gondwana <brong@fastmail.fm> Cc: Ethan Solomita <solo@google.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: WU Fengguang <wfg@mail.ustc.edu.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Documentation: update hugetlb informationNishanth Aravamudan2007-12-171-0/+19
| | | | | | | | | | | | | | | The hugetlb documentation has gotten a bit out of sync with the current code. Updated the sysctl file to refer to Documentation/vm/hugetlbpage.txt. Update that file to contain the current state of affairs (with the newer named sysctl in place). Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com> Acked-by: Adam Litke <agl@us.ibm.com> Cc: William Lee Irwin III <wli@holomorphy.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* vm.txt: document min_free_pages as critical for correctnessPavel Machek2007-10-171-0/+6
| | | | | | | | min_free_pages is critical for correctness, document it as such. Signed-off-by: Pavel Machek <pavel@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Add a 00-INDEX file to Documentation/sysctl/Jesper Juhl2007-10-171-0/+16
| | | | | | | | | | Add a 00-INDEX file to Documentation/sysctl/ Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com> Cc: Rob Landley <rob@landley.net> Cc: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* softlockup: add a /proc tuning parameterRavikiran G Thirumalai2007-10-171-0/+8
| | | | | | | | | | | | | | | | | | Control the trigger limit for softlockup warnings. This is useful for debugging softlockups, by lowering the softlockup_thresh to identify possible softlockups earlier. This patch: 1. Adds a sysctl softlockup_thresh with valid values of 1-60s (Higher value to disable false positives) 2. Changes the softlockup printk to print the cpu softlockup time [akpm@linux-foundation.org: Fix various warnings and add definition of "two"] Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org> Signed-off-by: Shai Fultheim <shai@scalex86.org> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* oom: add oom_kill_allocating_task sysctlDavid Rientjes2007-10-171-0/+22
| | | | | | | | | | | | | | Adds a new sysctl, 'oom_kill_allocating_task', which will automatically kill the OOM-triggering task instead of scanning through the tasklist to find a memory-hogging target. This is helpful for systems with an insanely large number of tasks where scanning the tasklist significantly degrades performance. Cc: Andrea Arcangeli <andrea@suse.de> Acked-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* handle kernelcore=: genericMel Gorman2007-07-171-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | This patch adds the kernelcore= parameter for x86. Once all patches are applied, a new command-line parameter exist and a new sysctl. This patch adds the necessary documentation. From: Yasunori Goto <y-goto@jp.fujitsu.com> When "kernelcore" boot option is specified, kernel can't boot up on ia64 because of an infinite loop. In addition, the parsing code can be handled in an architecture-independent manner. This patch uses common code to handle the kernelcore= parameter. It is only available to architectures that support arch-independent zone-sizing (i.e. define CONFIG_ARCH_POPULATES_NODE_MAP). Other architectures will ignore the boot parameter. [bunk@stusta.de: make cmdline_parse_kernelcore() static] Signed-off-by: Mel Gorman <mel@csn.ul.ie> Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com> Acked-by: Andy Whitcroft <apw@shadowen.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Add Documentation/sysctl/ctl_unnumbered.txtAndrew Morton2007-07-161-0/+22
| | | | | | | | | | | | | | Poeple keep on adding new numbered sysctls, when they're supposed not to. Add a documentation file which explain why new sysctls should use CTL_UNNUMBERED. The next patch will sprinkle pointers to this throughout sysctl.c. Eric provided the text (thanks) Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* change zonelist order: zonelist order selection logicKAMEZAWA Hiroyuki2007-07-161-0/+45
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make zonelist creation policy selectable from sysctl/boot option v6. This patch makes NUMA's zonelist (of pgdat) order selectable. Available order are Default(automatic)/ Node-based / Zone-based. [Default Order] The kernel selects Node-based or Zone-based order automatically. [Node-based Order] This policy treats the locality of memory as the most important parameter. Zonelist order is created by each zone's locality. This means lower zones (ex. ZONE_DMA) can be used before higher zone (ex. ZONE_NORMAL) exhausion. IOW. ZONE_DMA will be in the middle of zonelist. current 2.6.21 kernel uses this. Pros. * A user can expect local memory as much as possible. Cons. * lower zone will be exhansted before higher zone. This may cause OOM_KILL. Maybe suitable if ZONE_DMA is relatively big and you never see OOM_KILL because of ZONE_DMA exhaution and you need the best locality. (example) assume 2 node NUMA. node(0) has ZONE_DMA/ZONE_NORMAL, node(1) has ZONE_NORMAL. *node(0)'s memory allocation order: node(0)'s NORMAL -> node(0)'s DMA -> node(1)'s NORMAL. *node(1)'s memory allocation order: node(1)'s NORMAL -> node(0)'s NORMAL -> node(0)'s DMA. [Zone-based order] This policy treats the zone type as the most important parameter. Zonelist order is created by zone-type order. This means lower zone never be used bofere higher zone exhaustion. IOW. ZONE_DMA will be always at the tail of zonelist. Pros. * OOM_KILL(bacause of lower zone) occurs only if the whole zones are exhausted. Cons. * memory locality may not be best. (example) assume 2 node NUMA. node(0) has ZONE_DMA/ZONE_NORMAL, node(1) has ZONE_NORMAL. *node(0)'s memory allocation order: node(0)'s NORMAL -> node(1)'s NORMAL -> node(0)'s DMA. *node(1)'s memory allocation order: node(1)'s NORMAL -> node(0)'s NORMAL -> node(0)'s DMA. bootoption "numa_zonelist_order=" and proc/sysctl is supporetd. command: %echo N > /proc/sys/vm/numa_zonelist_order Will rebuild zonelist in Node-based order. command: %echo Z > /proc/sys/vm/numa_zonelist_order Will rebuild zonelist in Zone-based order. Thanks to Lee Schermerhorn, he gives me much help and codes. [Lee.Schermerhorn@hp.com: add check_highest_zone to build_zonelists_in_zone_order] [akpm@linux-foundation.org: build fix] Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Lee Schermerhorn <lee.schermerhorn@hp.com> Cc: Christoph Lameter <clameter@sgi.com> Cc: Andi Kleen <ak@suse.de> Cc: "jesse.barnes@intel.com" <jesse.barnes@intel.com> Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* security: Protection for exploiting null dereference using mmapEric Paris2007-07-111-0/+15
| | | | | | | | | | | | | | | | | | | | | Add a new security check on mmap operations to see if the user is attempting to mmap to low area of the address space. The amount of space protected is indicated by the new proc tunable /proc/sys/vm/mmap_min_addr and defaults to 0, preserving existing behavior. This patch uses a new SELinux security class "memprotect." Policy already contains a number of allow rules like a_t self:process * (unconfined_t being one of them) which mean that putting this check in the process class (its best current fit) would make it useless as all user processes, which we also want to protect against, would be allowed. By taking the memprotect name of the new class it will also make it possible for us to move some of the other memory protect permissions out of 'process' and into the new class next time we bump the policy version number (which I also think is a good future idea) Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Acked-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* misc doc and kconfig typosMatt LaPlante2007-05-091-1/+1
| | | | | | | Fix various typos in kernel docs and Kconfigs, 2.6.21-rc4. Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com> Signed-off-by: Adrian Bunk <bunk@stusta.de>
* Fix misspellings collected by members of KJ list.Robert P. J. Day2007-05-091-1/+1
| | | | | | | | Fix the misspellings of "propogate", "writting" and (oh, the shame :-) "kenrel" in the source tree. Signed-off-by: Robert P. J. Day <rpjday@mindspring.com> Signed-off-by: Adrian Bunk <bunk@stusta.de>
* mm: fix handling of panic_on_oom when cpusets are in useYasunori Goto2007-05-071-6/+17
| | | | | | | | | | | | | | | | | | The current panic_on_oom may not work if there is a process using cpusets/mempolicy, because other nodes' memory may remain. But some people want failover by panic ASAP even if they are used. This patch makes new setting for its request. This is tested on my ia64 box which has 3 nodes. Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com> Signed-off-by: Benjamin LaHaise <bcrl@kvack.org> Cc: Christoph Lameter <clameter@sgi.com> Cc: Paul Jackson <pj@sgi.com> Cc: Ethan Solomita <solo@google.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] x86: add sysctl for kstack_depth_to_printChuck Ebbert2006-12-071-0/+8
| | | | | | | | | Add sysctl for kstack_depth_to_print. This lets users change the amount of raw stack data printed in dump_stack() without having to reboot. Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com> Signed-off-by: Andi Kleen <ak@suse.de>
* Fix typos in /Documentation : MiscMatt LaPlante2006-11-302-2/+2
| | | | | | | | | This patch fixes typos in various Documentation txts. The patch addresses some misc words. Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com> Acked-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Adrian Bunk <bunk@stusta.de>
* [PATCH] document the core-dump-to-a-pipe patchMatthias Urlichs2006-10-111-1/+4
| | | | | | | | | | | | | The pipe-a-coredump-to-a-program feature was undocumented. *Grumble*. NB: a good enhancement to that patch would be: save all the stuff that a core file can get from the %x expansions in the environment. Signed-off-by: Matthias Urlichs <matthias@urlichs.de> Cc: Andi Kleen <ak@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] zone_reclaim: dynamic slab reclaimChristoph Lameter2006-09-261-7/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently one can enable slab reclaim by setting an explicit option in /proc/sys/vm/zone_reclaim_mode. Slab reclaim is then used as a final option if the freeing of unmapped file backed pages is not enough to free enough pages to allow a local allocation. However, that means that the slab can grow excessively and that most memory of a node may be used by slabs. We have had a case where a machine with 46GB of memory was using 40-42GB for slab. Zone reclaim was effective in dealing with pagecache pages. However, slab reclaim was only done during global reclaim (which is a bit rare on NUMA systems). This patch implements slab reclaim during zone reclaim. Zone reclaim occurs if there is a danger of an off node allocation. At that point we 1. Shrink the per node page cache if the number of pagecache pages is more than min_unmapped_ratio percent of pages in a zone. 2. Shrink the slab cache if the number of the nodes reclaimable slab pages (patch depends on earlier one that implements that counter) are more than min_slab_ratio (a new /proc/sys/vm tunable). The shrinking of the slab cache is a bit problematic since it is not node specific. So we simply calculate what point in the slab we want to reach (current per node slab use minus the number of pages that neeed to be allocated) and then repeately run the global reclaim until that is unsuccessful or we have reached the limit. I hope we will have zone based slab reclaim at some point which will make that easier. The default for the min_slab_ratio is 5% Also remove the slab option from /proc/sys/vm/zone_reclaim_mode. [akpm@osdl.org: cleanups] Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] Fix docs for fs.suid_dumpableAlexey Dobriyan2006-08-272-20/+20
| | | | | | | | | | | 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 <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] doc: update panic_on_oops documentationMaxime Bizon2006-08-061-3/+2
| | | | | | | Signed-off-by: Maxime Bizon <mbizon@freebox.fr> Acked-by: Simon Horman <horms@verge.net.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] ZVC/zone_reclaim: Leave 1% of unmapped pagecache pages for file I/OChristoph Lameter2006-07-031-0/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] zoned vm counters: zone_reclaim: remove ↵Christoph Lameter2006-06-301-13/+0
| | | | | | | | | | | | | | | | | | | /proc/sys/vm/zone_reclaim_interval 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 <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] support for panic at OOMKAMEZAWA Hiroyuki2006-06-231-0/+13
| | | | | | | | | | | | | | | | | 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 <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] suspend-to-ram: allow video options to be set at runtimePavel Machek2006-02-201-0/+10
| | | | | | | | | | | | | | | | | | 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 <pavel@suse.cz> Cc: "Brown, Len" <len.brown@intel.com> Cc: "Antonino A. Daplas" <adaplas@pol.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] Reclaim slab during zone reclaimChristoph Lameter2006-02-011-0/+6
| | | | | | | | | | | | | | | | | | | 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 <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] Zone reclaim: Allow modification of zone reclaim behaviorChristoph Lameter2006-02-011-8/+30
| | | | | | | | | | | | | | | | | | 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 <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] zone_reclaim: configurable off node allocation period.Christoph Lameter2006-02-011-0/+12
| | | | | | | | | | | | | | | | | | | 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 <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] Zone reclaim: proc overrideChristoph Lameter2006-01-181-0/+18
| | | | | | | | | | | | 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 <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] Make high and batch sizes of per_cpu_pagelists configurableRohit Seth2006-01-081-0/+17
| | | | | | | | | | | | | | | | | | | As recently there has been lot of traffic on the right values for batch and high water marks for per_cpu_pagelists. This patch makes these two variables configurable through /proc interface. A new tunable /proc/sys/vm/percpu_pagelist_fraction is added. This entry controls the fraction of pages at most in each zone that are allocated for each per cpu page list. The min value for this is 8. It means that we don't allow more than 1/8th of pages in each zone to be allocated in any single per_cpu_pagelist. The batch value of each per cpu pagelist is also updated as a result. It is set to pcp->high/4. The upper limit of batch is (PAGE_SHIFT * 8) Signed-off-by: Rohit Seth <rohit.seth@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] drop-pagecacheAndrew Morton2006-01-081-1/+2
| | | | | | | | | | | | | | | | | | | | | | Add /proc/sys/vm/drop_caches. When written to, this will cause the kernel to discard as much pagecache and/or reclaimable slab objects as it can. THis operation requires root permissions. It won't drop dirty data, so the user should run `sync' first. Caveats: a) Holds inode_lock for exorbitant amounts of time. b) Needs to be taught about NUMA nodes: propagate these all the way through so the discarding can be controlled on a per-node basis. This is a debugging feature: useful for getting consistent results between filesystem benchmarks. We could possibly put it under a config option, but it's less than 300 bytes. Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] setuid core dumpAlan Cox2005-06-231-0/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a new `suid_dumpable' sysctl: This value can be used to query and set the core dump mode for setuid or otherwise protected/tainted binaries. The modes are 0 - (default) - traditional behaviour. Any process which has changed privilege levels or is execute only will not be dumped 1 - (debug) - all processes dump core when possible. The core dump is owned by the current user and no security is applied. This is intended for system debugging situations only. Ptrace is unchecked. 2 - (suidsafe) - any binary which normally would not be dumped is dumped readable by root only. This allows the end user to remove such a dump but not access it directly. For security reasons core dumps in this mode will not overwrite one another or other files. This mode is appropriate when adminstrators are attempting to debug problems in a normal environment. (akpm: > > +EXPORT_SYMBOL(suid_dumpable); > > EXPORT_SYMBOL_GPL? No problem to me. > > if (current->euid == current->uid && current->egid == current->gid) > > current->mm->dumpable = 1; > > Should this be SUID_DUMP_USER? Actually the feedback I had from last time was that the SUID_ defines should go because its clearer to follow the numbers. They can go everywhere (and there are lots of places where dumpable is tested/used as a bool in untouched code) > Maybe this should be renamed to `dump_policy' or something. Doing that > would help us catch any code which isn't using the #defines, too. Fair comment. The patch was designed to be easy to maintain for Red Hat rather than for merging. Changing that field would create a gigantic diff because it is used all over the place. ) Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds2005-04-166-0/+717
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-15 22:36:58 +0000