topic Disk excercice in Operating System - HP-UX

Disk excercice

farhi — Mon, 13 Nov 2000 09:55:12 GMT

Thank you for your answering, but my question is very specific: which of the following commands "cat, cp, mv and more" can excercice the Disk without harm data.

Re: Disk excercice

Stefan Farrelly — Mon, 13 Nov 2000 10:12:27 GMT

cat or cp. If you cp or cat the files to /dev/null that should exercies the read element of your disk. I would use cp, cat may pick up control characters in some files and thus do some strange things to your display.

Re: Disk excercice

CHRIS_ANORUO — Mon, 13 Nov 2000 10:12:47 GMT

dd will exercise your disk without harm to data
mv will move your data to another specified area.
cp does not exercise disk as dd does and it does not destroy data
cat and more will allow you to page file information for viewing and will not
damage data unless binary and machine file. I will advise that you use 'file'
before using vi to check the file if you don't really know the file format

Re: Disk excercice

Andreas Voss — Mon, 13 Nov 2000 10:15:41 GMT

Hi,

i'm not clear what you want.
Why exercising with cat,mv,cp, more ?
Do you want to read from disk device or filesystem ?
All 4 commands can be used to read or write from/to a file.
Writing to device is very dangerous.
Read will never harm any data.

Regards

Re: Disk excercice

Carol Garrett — Mon, 13 Nov 2000 11:04:28 GMT

Agreed cp is not as good as dd but thats not the question, the question was which of those commands is best to use for disk exercising. Using time cp to copy all the files on an lvol/disk to /dev/null would still be a good exerciser of a disks read speed, eg;

cd /tmp
time find . -type f -exec cp /dev/null {} \;