<html><head><style type='text/css'>p { margin: 0; }</style></head><body><div style='font-family: Arial; font-size: 12pt; color: #000000'>Absolutely, If I can get back to the office I'll even do it tonight, otherwise it might be tomorrow. <div><br></div><div>Thanks for your help</div><div><br>----- Original Message -----<br>From: "Greg Freemyer" <greg.freemyer@gmail.com><br>To: "Atlanta Linux Enthusiasts - Yes! We run Linux!" <ale@ale.org><br>Sent: Thursday, October 29, 2009 6:34:24 PM GMT -05:00 US/Canada Eastern<br>Subject: Re: [ale] Disk IO Question<br><br>Can you comment on / answer the rest of my post?<br><br>> 60 GB per hour may or may not be slow. If the files are very small, I<br>> find 100K files / hr to be a limiting factor in some cases.<br>><br>So how many files per hour are you currently seeing?<br><br>> I also do a lot of "dd if=/dev/sdb of=/dev/sdc bs=4k<br>> conv=noerror,sync" copying of filesystems. I see speeds of 250GB/hr<br>> even with just drive to drive transfers. You raid array should be<br>> much faster.<br><br>Even as a test can try this? If you don't unmap the source array, the<br>dest will not be a good copy, but this would still be a good<br>performance test.<br><br>> So if you can unmount your primary drive every night, you should be<br>> able to make a dd copy every night. I have one vendor that is telling<br>> me they are moving data around at 1TB/hr. (I'm not sure how true that<br>> is.)<br><br>If unmounting every night is a problem, consider LVM snapshots? They<br>allow you to make a "point-in-time" copy that requires hours to<br>actually make.<br><br>Greg<br>_______________________________________________<br>Ale mailing list<br>Ale@ale.org<br>http://mail.ale.org/mailman/listinfo/ale<br>See JOBS, ANNOUNCE and SCHOOLS lists at<br>http://mail.ale.org/mailman/listinfo<br></div></div></body></html>