Fluctuating Server Load - Can't kill process

I'm getting really high fluctuating server loads which appear to build really high and then die down all day long. I notice in "top" a few httpd processes owned by "nobody" which seems to hang around for hours gradually using more cpu. I can't kill these processes in top either!

Could this be a hacker?

Processor #1 Vendor: GenuineIntelProcessor #1 Name: Intel(R) Xeon(TM) CPU 2.80GHzProcessor #1 speed: 2799.282 MHzProcessor #1 cache size: 512 KBProcessor #2 Vendor: GenuineIntelProcessor #2 Name: Intel(R) Xeon(TM) CPU 2.80GHzProcessor #2 speed: 2799.282 MHzProcessor #2 cache size: 512 KBProcessor #3 Vendor: GenuineIntelProcessor #3 Name: Intel(R) Xeon(TM) CPU 2.80GHzProcessor #3 speed: 2799.282 MHzProcessor #3 cache size: 512 KBProcessor #4 Vendor: GenuineIntelProcessor #4 Name: Intel(R) Xeon(TM) CPU 2.80GHzProcessor #4 speed: 2799.282 MHzProcessor #4 cache size: 512 KB

Memory InformationMemory: 1005828k/1032192k available (1727k kernel code, 22904k reserved, 1304k data, 228k init, 114688k highmem)

System InformationLinux grrl.pcmama.co.uk 2.4.21-40.ELsmp #1 SMP Thu Feb 2 22:22:39 EST 2006 i686 i686 i386 GNU/Linux

Physcial Diskshda: HDS722512VLAT20, ATA DISK drivehdc: CD-224E, ATAPI CD/DVD-ROM drivehdd: HDS722512VLAT20, ATA DISK drivehda: attached ide-disk driver.hda: host protected area => 1hda: 241254720 sectors (123522 MB) w/1794KiB Cache, CHS=15017/255/63, UDMA(100)hdd: attached ide-disk driver.hdd: host protected area => 1hdd: 241254720 sectors (123522 MB) w/1794KiB Cache, CHS=15017/255/63, UDMA(100)

Current Memory Usage total used free shared buffers cachedMem: 1009292 975108 34184 0 31460 497360-/+ buffers/cache: 446288 563004Swap: 2040212 206892 1833320Total: 3049504 1182000 1867504

Current Disk UsageFilesystem Size Used Avail Use% Mounted on/dev/hda6 1012M 608M 353M 64% //dev/hdd1 114G 96G 13G 89% /backup/dev/hda1 99M 37M 58M 39% /boot/dev/hda5 93G 18G 71G 20% /homenone 493M 0 493M 0% /dev/shm/dev/hda7 1012M 104M 857M 11% /tmp/dev/hda2 9.9G 5.3G 4.2G 56% /usr/dev/hda3 6.9G 3.1G 3.6G 47% /var

 

 

 

 

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