diff options
author | Dan Williams <dan.j.williams@intel.com> | 2009-09-08 17:55:21 -0700 |
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committer | Dan Williams <dan.j.williams@intel.com> | 2009-09-08 17:55:21 -0700 |
commit | bbb20089a3275a19e475dbc21320c3742e3ca423 (patch) | |
tree | 216fdc1cbef450ca688135c5b8969169482d9a48 /Documentation/sysctl/vm.txt | |
parent | 3e48e656903e9fd8bc805c6a2c4264d7808d315b (diff) | |
parent | 657a77fa7284d8ae28dfa48f1dc5d919bf5b2843 (diff) |
Merge branch 'dmaengine' into async-tx-next
Conflicts:
crypto/async_tx/async_xor.c
drivers/dma/ioat/dma_v2.h
drivers/dma/ioat/pci.c
drivers/md/raid5.c
Diffstat (limited to 'Documentation/sysctl/vm.txt')
-rw-r--r-- | Documentation/sysctl/vm.txt | 27 |
1 files changed, 16 insertions, 11 deletions
diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt index c302ddf629a..c4de6359d44 100644 --- a/Documentation/sysctl/vm.txt +++ b/Documentation/sysctl/vm.txt @@ -233,8 +233,8 @@ These protections are added to score to judge whether this zone should be used for page allocation or should be reclaimed. In this example, if normal pages (index=2) are required to this DMA zone and -pages_high is used for watermark, the kernel judges this zone should not be -used because pages_free(1355) is smaller than watermark + protection[2] +watermark[WMARK_HIGH] is used for watermark, the kernel judges this zone should +not be used because pages_free(1355) is smaller than watermark + protection[2] (4 + 2004 = 2008). If this protection value is 0, this zone would be used for normal page requirement. If requirement is DMA zone(index=0), protection[0] (=0) is used. @@ -280,9 +280,10 @@ The default value is 65536. min_free_kbytes: This is used to force the Linux VM to keep a minimum number -of kilobytes free. The VM uses this number to compute a pages_min -value for each lowmem zone in the system. Each lowmem zone gets -a number of reserved free pages based proportionally on its size. +of kilobytes free. The VM uses this number to compute a +watermark[WMARK_MIN] value for each lowmem zone in the system. +Each lowmem zone gets a number of reserved free pages based +proportionally on its size. Some minimal amount of memory is needed to satisfy PF_MEMALLOC allocations; if you set this to lower than 1024KB, your system will @@ -314,10 +315,14 @@ min_unmapped_ratio: This is available only on NUMA kernels. -A percentage of the total pages in each zone. Zone reclaim will only -occur if more than this percentage of pages are file backed and unmapped. -This is to insure that a minimal amount of local pages is still available for -file I/O even if the node is overallocated. +This is a percentage of the total pages in each zone. Zone reclaim will +only occur if more than this percentage of pages are in a state that +zone_reclaim_mode allows to be reclaimed. + +If zone_reclaim_mode has the value 4 OR'd, then the percentage is compared +against all file-backed unmapped pages including swapcache pages and tmpfs +files. Otherwise, only unmapped pages backed by normal files but not tmpfs +files and similar are considered. The default is 1 percent. @@ -358,7 +363,7 @@ nr_pdflush_threads The current number of pdflush threads. This value is read-only. The value changes according to the number of dirty pages in the system. -When neccessary, additional pdflush threads are created, one per second, up to +When necessary, additional pdflush threads are created, one per second, up to nr_pdflush_threads_max. ============================================================== @@ -565,7 +570,7 @@ swappiness This control is used to define how aggressive the kernel will swap memory pages. Higher values will increase agressiveness, lower values -descrease the amount of swap. +decrease the amount of swap. The default value is 60. |