| 1 | From d620f695290e4ffb1586420ba1dbbb5b2c8c075d Mon Sep 17 00:00:00 2001 |
| 2 | From: =?utf-8?q?Arve=20Hj=C3=B8nnev=C3=A5g?= <arve@android.com> |
| 3 | Date: Tue, 17 Feb 2009 14:51:02 -0800 |
| 4 | Subject: [PATCH 055/134] mm: Add min_free_order_shift tunable. |
| 5 | MIME-Version: 1.0 |
| 6 | Content-Type: text/plain; charset=utf-8 |
| 7 | Content-Transfer-Encoding: 8bit |
| 8 | |
| 9 | By default the kernel tries to keep half as much memory free at each |
| 10 | order as it does for one order below. This can be too agressive when |
| 11 | running without swap. |
| 12 | |
| 13 | Signed-off-by: Arve Hjønnevåg <arve@android.com> |
| 14 | --- |
| 15 | kernel/sysctl.c | 9 +++++++++ |
| 16 | mm/page_alloc.c | 3 ++- |
| 17 | 2 files changed, 11 insertions(+), 1 deletions(-) |
| 18 | |
| 19 | --- a/kernel/sysctl.c |
| 20 | +++ b/kernel/sysctl.c |
| 21 | @@ -77,6 +77,7 @@ extern int suid_dumpable; |
| 22 | extern char core_pattern[]; |
| 23 | extern int pid_max; |
| 24 | extern int min_free_kbytes; |
| 25 | +extern int min_free_order_shift; |
| 26 | extern int pid_max_min, pid_max_max; |
| 27 | extern int sysctl_drop_caches; |
| 28 | extern int percpu_pagelist_fraction; |
| 29 | @@ -1138,6 +1139,14 @@ static struct ctl_table vm_table[] = { |
| 30 | .extra1 = &zero, |
| 31 | }, |
| 32 | { |
| 33 | + .ctl_name = CTL_UNNUMBERED, |
| 34 | + .procname = "min_free_order_shift", |
| 35 | + .data = &min_free_order_shift, |
| 36 | + .maxlen = sizeof(min_free_order_shift), |
| 37 | + .mode = 0644, |
| 38 | + .proc_handler = &proc_dointvec |
| 39 | + }, |
| 40 | + { |
| 41 | .ctl_name = VM_PERCPU_PAGELIST_FRACTION, |
| 42 | .procname = "percpu_pagelist_fraction", |
| 43 | .data = &percpu_pagelist_fraction, |
| 44 | --- a/mm/page_alloc.c |
| 45 | +++ b/mm/page_alloc.c |
| 46 | @@ -119,6 +119,7 @@ static char * const zone_names[MAX_NR_ZO |
| 47 | }; |
| 48 | |
| 49 | int min_free_kbytes = 1024; |
| 50 | +int min_free_order_shift = 1; |
| 51 | |
| 52 | unsigned long __meminitdata nr_kernel_pages; |
| 53 | unsigned long __meminitdata nr_all_pages; |
| 54 | @@ -1258,7 +1259,7 @@ int zone_watermark_ok(struct zone *z, in |
| 55 | free_pages -= z->free_area[o].nr_free << o; |
| 56 | |
| 57 | /* Require fewer higher order pages to be free */ |
| 58 | - min >>= 1; |
| 59 | + min >>= min_free_order_shift; |
| 60 | |
| 61 | if (free_pages <= min) |
| 62 | return 0; |
| 63 | |
