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Diffstat (limited to 'Documentation/sysctl')
-rw-r--r-- | Documentation/sysctl/vm.txt | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt index 89ba1a42a17d..6910c0136f8d 100644 --- a/Documentation/sysctl/vm.txt +++ b/Documentation/sysctl/vm.txt | |||
@@ -103,3 +103,20 @@ This is used to force the Linux VM to keep a minimum number | |||
103 | of kilobytes free. The VM uses this number to compute a pages_min | 103 | of kilobytes free. The VM uses this number to compute a pages_min |
104 | value for each lowmem zone in the system. Each lowmem zone gets | 104 | value for each lowmem zone in the system. Each lowmem zone gets |
105 | a number of reserved free pages based proportionally on its size. | 105 | a number of reserved free pages based proportionally on its size. |
106 | |||
107 | ============================================================== | ||
108 | |||
109 | percpu_pagelist_fraction | ||
110 | |||
111 | This is the fraction of pages at most (high mark pcp->high) in each zone that | ||
112 | are allocated for each per cpu page list. The min value for this is 8. It | ||
113 | means that we don't allow more than 1/8th of pages in each zone to be | ||
114 | allocated in any single per_cpu_pagelist. This entry only changes the value | ||
115 | of hot per cpu pagelists. User can specify a number like 100 to allocate | ||
116 | 1/100th of each zone to each per cpu page list. | ||
117 | |||
118 | The batch value of each per cpu pagelist is also updated as a result. It is | ||
119 | set to pcp->high/4. The upper limit of batch is (PAGE_SHIFT * 8) | ||
120 | |||
121 | The initial value is zero. Kernel does not use this value at boot time to set | ||
122 | the high water marks for each per cpu page list. | ||