Difference between revisions of "Memory management"
From Linuxintro
imported>ThorstenStaerk |
imported>ThorstenStaerk |
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| Line 7: | Line 7: | ||
* https://fedorahosted.org/libpagemap/ | * https://fedorahosted.org/libpagemap/ | ||
| + | = page size = | ||
| + | Ok, first I want to find out my system's page size so I write a program: | ||
| + | #include <unistd.h> | ||
| + | #include <stdio.h> | ||
| + | int main() | ||
| + | { | ||
| + | int sz = getpagesize(); | ||
| + | printf("%d",sz); | ||
| + | } | ||
| + | And compile it: | ||
| + | # gcc main.c | ||
| + | And execute it: | ||
| + | # ./a.out | ||
| + | 4096 | ||
| + | Ok, so my system's page size is 4K. | ||
<pre> | <pre> | ||
# pmap 24058 | # pmap 24058 | ||
Revision as of 09:23, 6 June 2012
- http://linux-mm.org
- http://linux-mm.org/Low_On_Memory
- http://www.linux.com/learn/tutorials/42048-uncover-the-meaning-of-tops-statistics
- http://en.wikipedia.org/wiki/Resident_set_size
- http://en.wikipedia.org/wiki/Mmap
- http://lwn.net/Articles/230975/
- https://fedorahosted.org/libpagemap/
page size
Ok, first I want to find out my system's page size so I write a program:
#include <unistd.h>
#include <stdio.h>
int main()
{
int sz = getpagesize();
printf("%d",sz);
}
And compile it:
# gcc main.c
And execute it:
# ./a.out 4096
Ok, so my system's page size is 4K.
# pmap 24058
24058: a.out
START SIZE RSS PSS DIRTY SWAP PERM MAPPING
0000000000400000 4K 4K 4K 0K 0K r-xp /home/tstaerk/test/a.out
0000000000600000 4K 4K 4K 4K 0K r--p /home/tstaerk/test/a.out
0000000000601000 4K 4K 4K 4K 0K rw-p /home/tstaerk/test/a.out
00007fda6f01e000 1364K 160K 1K 0K 0K r-xp /lib64/libc-2.11.1.so
00007fda6f173000 2044K 0K 0K 0K 0K ---p /lib64/libc-2.11.1.so
00007fda6f372000 16K 16K 16K 16K 0K r--p /lib64/libc-2.11.1.so
00007fda6f376000 4K 4K 4K 4K 0K rw-p /lib64/libc-2.11.1.so
00007fda6f377000 20K 12K 12K 12K 0K rw-p [anon]
00007fda6f37c000 124K 104K 1K 0K 0K r-xp /lib64/ld-2.11.1.so
00007fda6f55a000 12K 12K 12K 12K 0K rw-p [anon]
00007fda6f599000 4K 4K 4K 4K 0K rw-p [anon]
00007fda6f59a000 4K 4K 4K 4K 0K r--p /lib64/ld-2.11.1.so
00007fda6f59b000 4K 4K 4K 4K 0K rw-p /lib64/ld-2.11.1.so
00007fda6f59c000 4K 4K 4K 4K 0K rw-p [anon]
00007fff625e5000 84K 12K 12K 12K 0K rw-p [stack]
00007fff625ff000 4K 4K 0K 0K 0K r-xp [vdso]
ffffffffff600000 4K 0K 0K 0K 0K r-xp [vsyscall]
Total: 3704K 352K 86K 80K 0K
136K writable-private, 3568K readonly-private, 0K shared, and 352K referenced
# ldd a.out
linux-vdso.so.1 => (0x00007fffc4bee000)
libc.so.6 => /lib64/libc.so.6 (0x00007f2c6cc78000)
/lib64/ld-linux-x86-64.so.2 (0x00007f2c6d013000)
