For about 15 minutes or so after login on my FreeBSD 8.1 (yes, I know its not Linux) the hard drive goes absolutely crazy with activity. So much so that it takes a while for the ls command to read the contents of the directory. But after the 15 minutes or so the disk activity calms down and returns to normal.

Im thinking it is some sort of fsck command, but I am unsure where or how to disable it. The hard drive is connected via sata to the mobo. Im not quite sure what other info I can post to find out what is going on. Just tell me what other info is needed and Ill post it up.

Thanks for any help.

Ok, now the kernel just crashes after 15 mins of intense disk activity. The error message that appears is:

dev = ad4s1f, block = 1, fs = /usr
panic: ffs_blkfree: freeing free block
cpuid = 0
Uptime: 13m29s
Cannot dump. Device not defined or unavailable.
Automatic reboot in 15 seconds - press a key on the console to abort

It never does reboot. The hard drive is a 500 gig hard drive and it not full at all. Anyone know what is going on?

Can you run a check of the complete file system?

Yeah, I booted in to single user mode and fsck'ed every partition, not just ad4s1f and that seemed to fix everything.