If you're looking for a real-time graphical display, try GKrellm configured to show your USB drive's partition(s). This works fine in KDE as well as Gnome, BTW.
Is there a gkrellm rpm for CentOS 4? Can't seem to find one. Or do I need to get the source/compile/etc?
I tried iostat and I guess there is disk activity, but I have no idea if it's considered a lot or not, see below.
Thanks, James
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn sdb1 2.63 35.72 19.24 134576004 72488792
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn sdb1 15.50 1976.00 0.00 3952 0
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn sdb1 28.36 1954.23 23.88 3928 48
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn sdb1 11.50 2144.00 4.00 4288 8
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn sdb1 9.50 2176.00 0.00 4352 0
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn sdb1 12.50 1952.00 16.00 3904 32
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn sdb1 12.00 2080.00 0.00 4160 0
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn sdb1 9.00 2176.00 0.00 4352 0
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn sdb1 17.00 1920.00 56.00 3840 112
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn sdb1 10.05 2194.97 0.00 4368 0
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn sdb1 22.00 1956.00 20.00 3912 40
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn sdb1 13.93 1898.51 0.00 3816 0
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn sdb1 13.00 2072.00 0.00 4144 0
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn sdb1 15.50 2164.00 24.00 4328 48
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn sdb1 18.50 1988.00 0.00 3976 0
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn sdb1 11.94 1954.23 0.00 3928 0
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn sdb1 20.40 2089.55 23.88 4200 48
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn sdb1 15.50 1928.00 0.00 3856 0
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn sdb1 16.58 2142.71 28.14 4264 56
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn sdb1 15.00 2020.00 0.00 4040 0