Quadratic fsck

[Chuck Forsberg WA7KGX N2469R]

Forced fsck operations on huge filesystems (500GB) are
taking a very long time during bootup.  Some typical
situations:

/dev/sdb6            448936380 399105212  27026504  94% /w
/dev/sdc2            500028036 444954060  29674008  94% /v
/dev/sdc1            461404200 305735808 132230364  70% /y

How can I reduce this time?  Would converting these to ext4
speed up fsck?  Is converting to ext4 an option yet?

 Can something be done in the background
on a mounted file system to check it or at least minimize the
time it takes to run fsck on it?

-- 
Chuck Forsberg    caf at omen.com   www.omen.com   503-614-0430
Developer of Industrial ZMODEM(Tm) for Embedded Applications
  Omen Technology Inc      "The High Reliability Software"
10255 NW Old Cornelius Pass Portland OR 97231   FAX 629-0665