My VPS eats up RAM!

[Ademi]

My VPS with no domains works about 400Mb of RAM. here is the top command results. Please help me!

top - 14:15:17 up 11 min, 1 user, load average: 0.13, 0.05, 0.02
Mem: 524288k total, 415432k used, 108856k free, 0k buffers
Swap: 0k total, 0k used, 0k free, 0k cached

PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
1 root 20 0 2068 652 560 S 0.0 0.1 0:00.04 init
54 root 20 0 100 20 4 S 0.0 0.0 0:00.00 init-logger
107 root 16 -4 2152 524 344 S 0.0 0.1 0:00.00 udevd
414 root 20 0 1724 616 524 S 0.0 0.1 0:00.00 syslogd
433 root 20 0 7060 1060 664 S 0.0 0.2 0:00.00 sshd
444 root 20 0 2724 880 708 S 0.0 0.2 0:00.00 xinetd
459 root 20 0 5928 808 540 S 0.0 0.2 0:00.00 couriertcpd
461 root 20 0 4772 1052 820 S 0.0 0.2 0:00.00 courierlogger
469 root 20 0 5928 808 540 S 0.0 0.2 0:00.00 couriertcpd
471 root 20 0 4772 1052 820 S 0.0 0.2 0:00.00 courierlogger
477 root 20 0 5928 808 540 S 0.0 0.2 0:00.00 couriertcpd
479 root 20 0 4772 1048 820 S 0.0 0.2 0:00.00 courierlogger
486 root 20 0 5928 812 540 S 0.0 0.2 0:00.00 couriertcpd
488 root 20 0 4772 1056 820 S 0.0 0.2 0:00.00 courierlogger
500 qmails 20 0 1712 400 324 S 0.0 0.1 0:00.00 qmail-send
502 qmaill 20 0 1668 476 408 S 0.0 0.1 0:00.00 splogger
503 root 20 0 1696 356 268 S 0.0 0.1 0:00.00 qmail-lspawn
504 qmailr 20 0 1692 356 268 S 0.0 0.1 0:00.00 qmail-rspawn
505 qmailq 20 0 1660 344 284 S 0.0 0.1 0:00.00 qmail-clean
520 root 20 0 28604 10m 6248 S 0.0 2.0 0:00.08 httpd
566 named 20 0 90612 3244 1968 S 0.0 0.6 0:00.00 named
613 root 20 0 4528 1292 1128 S 0.0 0.2 0:00.00 mysqld_safe
659 apache 20 0 38152 15m 3708 S 0.0 2.9 0:00.48 httpd
660 apache 20 0 28740 5868 1428 S 0.0 1.1 0:00.00 httpd
661 apache 20 0 28740 5868 1428 S 0.0 1.1 0:00.00 httpd
662 apache 20 0 34564 11m 3460 S 0.0 2.2 0:00.14 httpd
663 apache 20 0 28740 5868 1428 S 0.0 1.1 0:00.00 httpd
664 apache 20 0 28740 5888 1448 S 0.0 1.1 0:00.00 httpd
665 apache 20 0 37232 13m 3608 S 0.0 2.7 0:00.14 httpd
666 apache 20 0 38144 15m 3684 S 0.0 2.9 0:00.20 httpd
671 mysql 20 0 95808 12m 4880 S 0.0 2.4 0:00.09 mysqld
735 postgres 20 0 21028 3312 2832 S 0.0 0.6 0:00.12 postmaster
737 postgres 20 0 10808 792 308 S 0.0 0.2 0:00.00 postmaster
751 postgres 20 0 21028 944 460 S 0.0 0.2 0:00.02 postmaster
752 postgres 20 0 11808 768 284 S 0.0 0.1 0:00.00 postmaster
753 postgres 20 0 11040 968 360 S 0.0 0.2 0:00.00 postmaster
756 root 20 0 34688 29m 2444 S 0.0 5.7 0:00.82 spamd
757 popuser 20 0 34688 28m 988 S 0.0 5.5 0:00.00 spamd
776 root 20 0 43688 6696 4184 S 0.0 1.3 0:00.02 httpsd
781 psaadm 20 0 48820 16m 11m S 0.0 3.3 0:00.46 httpsd
790 psaadm 20 0 49332 15m 9764 S 0.0 3.1 0:00.10 httpsd
792 drweb 20 0 35536 30m 496 S 0.0 5.9 0:00.00 drwebd.real
814 root 20 0 5284 1112 576 S 0.0 0.2 0:00.00 crond
824 mailman 20 0 13088 4944 772 S 0.0 0.9 0:00.00 mailmanctl
831 mailman 20 0 12984 6952 2780 S 0.0 1.3 0:00.14 python
832 mailman 20 0 12952 6976 2780 S 0.0 1.3 0:00.14 python
833 mailman 20 0 12928 6968 2780 S 0.0 1.3 0:00.12 python