Commenting out out_of_memory() function in __alloc_pages()

From: Abu M. Muttalib
Date: Fri Jul 07 2006 - 05:40:46 EST


Hi,

I am getting the Out of memory.

To circumvent the problem, I have commented the call to "out_of_memory(),
and replaced "goto restart" with "goto nopage".

At "nopage:" lable I have added a call to "schedule()" and then "return
NULL" after "schedule()".

I tried the modified kernel with a test application, the test application is
mallocing memory in a loop. Unlike as expected the process gets killed. On
second run of the same application I am getting the page allocation failure
as expected but subsequently the system hangs.

I am attaching the test application and the log herewith.

I am getting this exception with kernel 2.6.13. With kernel
2.4.19-rmka7-pxa1 there was no problem.

Why its so? What can I do to alleviate the OOM problem?

Thanks in anticipation and regards,
Abu.
sh-3.00# ./test1

OOM Test: Counter = 0
....
OOM Test: Counter = 6635
, OOM: Out of Memory would have been called....<4>test1: page allocation failure. order:0, mode:0xd2

Mem-info:

DMA per-cpu:

cpu 0 hot: low 2, high 6, batch 1 used:2

cpu 0 cold: low 0, high 2, batch 1 used:1

Normal per-cpu: empty

HighMem per-cpu: empty

Free pages: 588kB (0kB HighMem)

Active:2178 inactive:230 dirty:0 writeback:0 unstable:0 free:147 slab:367 mapped:2178 pagetables:43

DMA free:588kB min:512kB low:640kB high:768kB active:8712kB inactive:920kB present:16384kB pages_scanned:4851 all_unreclaimable? no

lowmem_reserve[]: 0 0 0

Normal free:0kB min:0kB low:0kB high:0kB active:0kB inactive:0kB present:0kB pages_scanned:0 all_unreclaimable? no

lowmem_reserve[]: 0 0 0

HighMem free:0kB min:128kB low:160kB high:192kB active:0kB inactive:0kB present:0kB pages_scanned:0 all_unreclaimable? no

lowmem_reserve[]: 0 0 0

DMA: 9*4kB 3*8kB 1*16kB 0*32kB 0*64kB 0*128kB 0*256kB 1*512kB 0*1024kB = 588kB

Normal: empty

HighMem: empty

Swap cache: add 0, delete 0, find 0/0, race 0+0

Free swap = 0kB

Total swap = 0kB

Free swap: 0kB

4096 pages of RAM

218 free pages

625 reserved pages

367 slab pages

0 pages shared

0 pages swap cached

VM: killing process test1

Killed
sh-3.00# ./test1

OOM Test: Counter = 0
....
OOM Test: Counter = 6416
, OOM: Out of Memory would have been called....<4>test1: page allocation failure. order:0, mode:0x201d0

Mem-info:

DMA per-cpu:

cpu 0 hot: low 2, high 6, batch 1 used:2

cpu 0 cold: low 0, high 2, batch 1 used:1

Normal per-cpu: empty

HighMem per-cpu: empty

Free pages: 672kB (0kB HighMem)

Active:2187 inactive:170 dirty:0 writeback:0 unstable:0 free:168 slab:365 mapped:2125 pagetables:43

DMA free:672kB min:512kB low:640kB high:768kB active:8748kB inactive:680kB present:16384kB pages_scanned:2939 all_unreclaimable? no

lowmem_reserve[]: 0 0 0

Normal free:0kB min:0kB low:0kB high:0kB active:0kB inactive:0kB present:0kB pages_scanned:0 all_unreclaimable? no

lowmem_reserve[]: 0 0 0

HighMem free:0kB min:128kB low:160kB high:192kB active:0kB inactive:0kB present:0kB pages_scanned:0 all_unreclaimable? no

lowmem_reserve[]: 0 0 0

DMA: 28*4kB 6*8kB 0*16kB 0*32kB 0*64kB 0*128kB 0*256kB 1*512kB 0*1024kB = 672kB

Normal: empty

HighMem: empty

Swap cache: add 0, delete 0, find 0/0, race 0+0

Free swap = 0kB

Total swap = 0kB

Free swap: 0kB

4096 pages of RAM

239 free pages

625 reserved pages

365 slab pages

13 pages shared

0 pages swap cached

Error -5 while decompressing!

c01e42f4(2388)->c0754000(4096)

Error -3 while decompressing!

c01e4c48(2531)->c0caf000(4096)

Error -3 while decompressing!

c01e562b(2643)->c0914000(4096)

, OOM: Out of Memory would have been called....<4>test1: page allocation failure. order:0, mode:0x201d2

Mem-info:

DMA per-cpu:

cpu 0 hot: low 2, high 6, batch 1 used:3

cpu 0 cold: low 0, high 2, batch 1 used:1

Normal per-cpu: empty

HighMem per-cpu: empty

Free pages: 600kB (0kB HighMem)

Active:2267 inactive:113 dirty:0 writeback:0 unstable:0 free:150 slab:365 mapped:2125 pagetables:43

DMA free:600kB min:512kB low:640kB high:768kB active:9068kB inactive:452kB present:16384kB pages_scanned:222 all_unreclaimable? no

lowmem_reserve[]: 0 0 0

Normal free:0kB min:0kB low:0kB high:0kB active:0kB inactive:0kB present:0kB pages_scanned:0 all_unreclaimable? no

lowmem_reserve[]: 0 0 0

HighMem free:0kB min:128kB low:160kB high:192kB active:0kB inactive:0kB present:0kB pages_scanned:0 all_unreclaimable? no

lowmem_reserve[]: 0 0 0

DMA: 22*4kB 0*8kB 0*16kB 0*32kB 0*64kB 0*128kB 0*256kB 1*512kB 0*1024kB = 600kB

Normal: empty

HighMem: empty

Swap cache: add 0, delete 0, find 0/0, race 0+0

Free swap = 0kB

Total swap = 0kB

Free swap: 0kB

4096 pages of RAM

222 free pages

625 reserved pages

365 slab pages

13 pages shared

0 pages swap cached

, OOM: Out of Memory would have been called....<4>init: page allocation failure. order:0, mode:0x201d0

Mem-info:

DMA per-cpu:

cpu 0 hot: low 2, high 6, batch 1 used:3

cpu 0 cold: low 0, high 2, batch 1 used:1

Normal per-cpu: empty

HighMem per-cpu: empty

Free pages: 696kB (0kB HighMem)

Active:2220 inactive:136 dirty:0 writeback:0 unstable:0 free:174 slab:365 mapped:2125 pagetables:43

DMA free:696kB min:512kB low:640kB high:768kB active:8880kB inactive:544kB present:16384kB pages_scanned:6729 all_unreclaimable? no

lowmem_reserve[]: 0 0 0

Normal free:0kB min:0kB low:0kB high:0kB active:0kB inactive:0kB present:0kB pages_scanned:0 all_unreclaimable? no

lowmem_reserve[]: 0 0 0

HighMem free:0kB min:128kB low:160kB high:192kB active:0kB inactive:0kB present:0kB pages_scanned:0 all_unreclaimable? no

lowmem_reserve[]: 0 0 0

DMA: 44*4kB 1*8kB 0*16kB 0*32kB 0*64kB 0*128kB 0*256kB 1*512kB 0*1024kB = 696kB

Normal: empty

HighMem: empty

Swap cache: add 0, delete 0, find 0/0, race 0+0

Free swap = 0kB

Total swap = 0kB

Free swap: 0kB

4096 pages of RAM

246 free pages

625 reserved pages

365 slab pages

3 pages shared

0 pages swap cached

Error -5 while decompressing!

c01e7949(2386)->c040d000(4096)

Error -3 while decompressing!

c01e829b(2297)->c05e9000(4096)

, OOM: Out of Memory would have been called....<4>init: page allocation failure. order:0, mode:0x201d2

Mem-info:

DMA per-cpu:

cpu 0 hot: low 2, high 6, batch 1 used:4

cpu 0 cold: low 0, high 2, batch 1 used:1

Normal per-cpu: empty

HighMem per-cpu: empty

Free pages: 600kB (0kB HighMem)

Active:2189 inactive:166 dirty:0 writeback:0 unstable:0 free:150 slab:364 mapped:2125 pagetables:43

DMA free:600kB min:512kB low:640kB high:768kB active:8756kB inactive:664kB present:16384kB pages_scanned:7675 all_unreclaimable? no

lowmem_reserve[]: 0 0 0

Normal free:0kB min:0kB low:0kB high:0kB active:0kB inactive:0kB present:0kB pages_scanned:0 all_unreclaimable? no

lowmem_reserve[]: 0 0 0

HighMem free:0kB min:128kB low:160kB high:192kB active:0kB inactive:0kB present:0kB pages_scanned:0 all_unreclaimable? no

lowmem_reserve[]: 0 0 0

DMA: 20*4kB 1*8kB 0*16kB 0*32kB 0*64kB 0*128kB 0*256kB 1*512kB 0*1024kB = 600kB

Normal: empty

HighMem: empty

Swap cache: add 0, delete 0, find 0/0, race 0+0

Free swap = 0kB

Total swap = 0kB

Free swap: 0kB

4096 pages of RAM

223 free pages

625 reserved pages

364 slab pages

1 pages shared

0 pages swap cached

, OOM: Out of Memory would have been called....<4>test1: page allocation failure. order:0, mode:0x201d0

Mem-info:

DMA per-cpu:

cpu 0 hot: low 2, high 6, batch 1 used:4

cpu 0 cold: low 0, high 2, batch 1 used:1

Normal per-cpu: empty

HighMem per-cpu: empty

Free pages: 600kB (0kB HighMem)

Active:2291 inactive:64 dirty:0 writeback:0 unstable:0 free:150 slab:364 mapped:2125 pagetables:43

DMA free:600kB min:512kB low:640kB high:768kB active:9164kB inactive:256kB present:16384kB pages_scanned:10106 all_unreclaimable? yes

lowmem_reserve[]: 0 0 0

Normal free:0kB min:0kB low:0kB high:0kB active:0kB inactive:0kB present:0kB pages_scanned:0 all_unreclaimable? no

lowmem_reserve[]: 0 0 0

HighMem free:0kB min:128kB low:160kB high:192kB active:0kB inactive:0kB present:0kB pages_scanned:0 all_unreclaimable? no

lowmem_reserve[]: 0 0 0

DMA: 20*4kB 1*8kB 0*16kB 0*32kB 0*64kB 0*128kB 0*256kB 1*512kB 0*1024kB = 600kB

Normal: empty

HighMem: empty

Swap cache: add 0, delete 0, find 0/0, race 0+0

Free swap = 0kB

Total swap = 0kB

Free swap: 0kB

4096 pages of RAM

223 free pages

625 reserved pages

364 slab pages

2 pages shared

0 pages swap cached

, OOM: Out of Memory would have been called....<4>init: page allocation failure. order:0, mode:0x201d2

Mem-info:

DMA per-cpu:

cpu 0 hot: low 2, high 6, batch 1 used:4

cpu 0 cold: low 0, high 2, batch 1 used:0

Normal per-cpu: empty

HighMem per-cpu: empty

Free pages: 512kB (0kB HighMem)

Active:2296 inactive:125 dirty:0 writeback:0 unstable:0 free:128 slab:364 mapped:2127 pagetables:43

DMA free:512kB min:512kB low:640kB high:768kB active:9184kB inactive:500kB present:16384kB pages_scanned:10106 all_unreclaimable? yes

lowmem_reserve[]: 0 0 0

Normal free:0kB min:0kB low:0kB high:0kB active:0kB inactive:0kB present:0kB pages_scanned:0 all_unreclaimable? no

lowmem_reserve[]: 0 0 0

HighMem free:0kB min:128kB low:160kB high:192kB active:0kB inactive:0kB present:0kB pages_scanned:0 all_unreclaimable? no

lowmem_reserve[]: 0 0 0

DMA: 0*4kB 0*8kB 0*16kB 0*32kB 0*64kB 0*128kB 0*256kB 1*512kB 0*1024kB = 512kB

Normal: empty

HighMem: empty

Swap cache: add 0, delete 0, find 0/0, race 0+0

Free swap = 0kB

Total swap = 0kB

Free swap: 0kB

4096 pages of RAM

200 free pages

625 reserved pages

364 slab pages

34 pages shared

0 pages swap cached

, OOM: Out of Memory would have been called....<4>init: page allocation failure. order:0, mode:0x201d2

Mem-info:

DMA per-cpu:

cpu 0 hot: low 2, high 6, batch 1 used:4

cpu 0 cold: low 0, high 2, batch 1 used:0

Normal per-cpu: empty

HighMem per-cpu: empty

Free pages: 512kB (0kB HighMem)

Active:2296 inactive:125 dirty:0 writeback:0 unstable:0 free:128 slab:364 mapped:2127 pagetables:43

DMA free:512kB min:512kB low:640kB high:768kB active:9184kB inactive:500kB present:16384kB pages_scanned:10106 all_unreclaimable? yes

lowmem_reserve[]: 0 0 0

Normal free:0kB min:0kB low:0kB high:0kB active:0kB inactive:0kB present:0kB pages_scanned:0 all_unreclaimable? no

lowmem_reserve[]: 0 0 0

HighMem free:0kB min:128kB low:160kB high:192kB active:0kB inactive:0kB present:0kB pages_scanned:0 all_unreclaimable? no

lowmem_reserve[]: 0 0 0

DMA: 0*4kB 0*8kB 0*16kB 0*32kB 0*64kB 0*128kB 0*256kB 1*512kB 0*1024kB = 512kB

Normal: empty

HighMem: empty

Swap cache: add 0, delete 0, find 0/0, race 0+0

Free swap = 0kB

Total swap = 0kB

Free swap: 0kB

4096 pages of RAM

200 free pages

625 reserved pages

364 slab pages

34 pages shared

0 pages swap cached

, OOM: Out of Memory would have been called....<4>test1: page allocation failure. order:0, mode:0x201d2

Mem-info:

DMA per-cpu:

cpu 0 hot: low 2, high 6, batch 1 used:4

cpu 0 cold: low 0, high 2, batch 1 used:0

Normal per-cpu: empty

HighMem per-cpu: empty

Free pages: 512kB (0kB HighMem)

Active:2296 inactive:125 dirty:0 writeback:0 unstable:0 free:128 slab:364 mapped:2133 pagetables:43

DMA free:512kB min:512kB low:640kB high:768kB active:9184kB inactive:500kB present:16384kB pages_scanned:10106 all_unreclaimable? yes

lowmem_reserve[]: 0 0 0

Normal free:0kB min:0kB low:0kB high:0kB active:0kB inactive:0kB present:0kB pages_scanned:0 all_unreclaimable? no

lowmem_reserve[]: 0 0 0

HighMem free:0kB min:128kB low:160kB high:192kB active:0kB inactive:0kB present:0kB pages_scanned:0 all_unreclaimable? no

lowmem_reserve[]: 0 0 0

DMA: 0*4kB 0*8kB 0*16kB 0*32kB 0*64kB 0*128kB 0*256kB 1*512kB 0*1024kB = 512kB

Normal: empty

HighMem: empty

Swap cache: add 0, delete 0, find 0/0, race 0+0

Free swap = 0kB

Total swap = 0kB

Free swap: 0kB

4096 pages of RAM

200 free pages

625 reserved pages

364 slab pages

40 pages shared

0 pages swap cached

, OOM: Out of Memory would have been called....VM: killing process test1





















Attachment: test1.c
Description: Binary data