flint@gistdev.gist.com (Flint Pellett) (07/21/90)
I found this line in the root crontab on our 3B2/600, which is now running R3.2.2. This smells a lot like a kludge fix/workaround to some sort of bug, but I've never heard of it before: it doesn't look like it can possibly be doing anything useful. 0 0 * * * dd if=/dev/mem of=/dev/null 2>/dev/null My questions are: 1. Why is it there? 2. Does it still need to be there? (Or is it there to fix a problem in a previous release which is now fixed right and doesn't need this?) -- Flint Pellett, Global Information Systems Technology, Inc. 1800 Woodfield Drive, Savoy, IL 61874 (217) 352-1165 uunet!gistdev!flint or flint@gistdev.gist.com
mdb@i88.isc.com (Mark Brukhartz) (07/22/90)
In article <932@gistdev.gist.com> flint@gistdev.gist.com (Flint Pellett) writes: >I found this line in the root crontab on our 3B2/600, which is now >running R3.2.2. [ ... ] > >0 0 * * * dd if=/dev/mem of=/dev/null 2>/dev/null It corrects single-bit memory errors before they grow into uncorrectable double-bit errors. The command, of course, reads all of physical memory. The memory hardware then detects any single- or double-bit errors and corrects the single-bit errors. Mark Brukhartz INTERACTIVE Systems Corporation Services and Technologies mdb@i88.isc.com ...!{amdahl, ico, ima, ism780c, masscomp, nucsrl, sun}!laidbak!mdb