Куда девается память?

top - 18:08:19 up 1 day, 20:31, 1 user, load average: 0.21, 0.19, 0.12
Tasks: 120 total, 1 running, 119 sleeping, 0 stopped, 0 zombie
Cpu(s): 9.0%us, 0.8%sy, 0.0%ni, 90.0%id, 0.2%wa, 0.0%hi, 0.0%si, 0.0%st
Mem: 1026860k total, 987676k used, 39184k free, 46084k buffers
Swap: 4192956k total, 276k used, 4192680k free, 715796k cached

PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
2369 mysql 15 0 151m 31m 4736 S 16 3.2 271:07.46 mysqld
31392 apache 16 0 34828 13m 4768 S 1 1.3 0:04.23 httpd
31120 apache 15 0 34736 13m 4864 S 1 1.3 0:05.41 httpd
31735 apache 16 0 34696 12m 4796 S 1 1.3 0:02.86 httpd
1792 named 18 0 51824 5620 2068 S 0 0.5 1:00.89 named
30236 root 18 0 31540 12m 7180 S 0 1.2 0:00.35 httpd
30288 apache 16 0 35344 13m 4828 S 0 1.4 0:08.01 httpd
31127 apache 15 0 35076 13m 4804 S 0 1.4 0:03.63 httpd
31405 apache 15 0 34700 13m 4796 S 0 1.3 0:04.72 httpd
1 root 15 0 2060 636 544 S 0 0.1 0:00.61 init
2 root RT -5 0 0 0 S 0 0.0 0:00.08 migration/0
3 root 34 19 0 0 0 S 0 0.0 0:00.00 ksoftirqd/0
4 root RT -5 0 0 0 S 0 0.0 0:00.00 watchdog/0
5 root RT -5 0 0 0 S 0 0.0 0:00.05 migration/1
6 root 34 19 0 0 0 S 0 0.0 0:00.00 ksoftirqd/1
7 root RT -5 0 0 0 S 0 0.0 0:00.00 watchdog/1
8 root 10 -5 0 0 0 S 0 0.0 0:00.00 events/0
9 root 10 -5 0 0 0 S 0 0.0 0:00.00 events/1
10 root 10 -5 0 0 0 S 0 0.0 0:00.00 khelper
11 root 10 -5 0 0 0 S 0 0.0 0:00.00 kthread
15 root 10 -5 0 0 0 S 0 0.0 0:00.09 kblockd/0
16 root 10 -5 0 0 0 S 0 0.0 0:00.05 kblockd/1
17 root 14 -5 0 0 0 S 0 0.0 0:00.00 kacpid
108 root 14 -5 0 0 0 S 0 0.0 0:00.00 cqueue/0
109 root 14 -5 0 0 0 S 0 0.0 0:00.00 cqueue/1
112 root 10 -5 0 0 0 S 0 0.0 0:00.00 khubd
114 root 10 -5 0 0 0 S 0 0.0 0:00.00 kseriod
180 root 15 0 0 0 0 S 0 0.0 0:00.00 pdflush
181 root 15 0 0 0 0 S 0 0.0 0:04.16 pdflush
182 root 10 -5 0 0 0 S 0 0.0 0:03.17 kswapd0
183 root 14 -5 0 0 0 S 0 0.0 0:00.00 aio/0
184 root 14 -5 0 0 0 S 0 0.0 0:00.00 aio/1
338 root 11 -5 0 0 0 S 0 0.0 0:00.00 kpsmoused
369 root 10 -5 0 0 0 S 0 0.0 0:00.00 ata/0
370 root 13 -5 0 0 0 S 0 0.0 0:00.00 ata/1
371 root 13 -5 0 0 0 S 0 0.0 0:00.00 ata_aux
375 root 10 -5 0 0 0 S 0 0.0 0:00.00 scsi_eh_0
376 root 10 -5 0 0 0 S 0 0.0 0:00.00 scsi_eh_1
377 root 10 -5 0 0 0 S 0 0.0 0:16.48 kjournald