You may be better off using smart, but if you want to go through all the blocks in a device without making your load skyrocket, I have two solutions for you: reblock (check the "-s" option): http://dcs.nac.uci.edu/~strombrg/reblock.html slowdown in combination with dd: http://dcs.nac.uci.edu/~strombrg/slowdown/ HTH :) On Tue, 2005-10-04 at 14:29 +0000, Andy Smith wrote: > Hello, > > I have a home fileserver with 4 SATA disks in a RAID 5. As I am > sure you are aware, SATA devices in Linux currently cannot be > queried for SMART info, so I can't do SMART health checks of these > devices. > > Also there is still the tendency for Linux Software RAID to kick > devices out of the array as soon as there is any error on them. > > I really don't want to be in the situation where a drive dies, I fit > a new one, and during the resync another device is kicked out > because of spontaneously finding a bad sector. > > I tried simply doing a > > dd if=/dev/sd[abcd] of=/dev/null > > To check each disk in a very unsubtle fashion, but it drives the > load average on the machine way way up (like to 20+) and makes it > very unresponsive (wait several minutes for a keypress to be > acknowledged), even if I run it under nice -n 19. > > I don't notice any performance problems on this server during normal > day to day use, and while it's not particularly beefy it is an AMD > Sempron 1.8GHz so I am surprised that simply reading from one disk > causes these performance issues. > > I know this isn't right, so has anyone got any advice in the way of > tracking down which part of the system is at fault, possibly > off-list if it's too offtopic? > > Thanks, > Andy - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
