heck yes, USB is slow overall. Sorry i didn't make it clear that i understood this.
as you may have noticed in the other message chain, I was wondering about "especially for random access", as opposed to just slow in general. i'd expect USB-attached drives to work relatively better for random-access than they do for bulk transfer. **In neither case would i expect them to be fast.** In the other sub-thread we went back and forth about this and decided it we both agreed usb sucked overall and it wasn't worth arguing about exactly how it sucked. :) danno On Mon, Sep 14, 2009 at 01:23:57PM +0200, Tino Schwarze wrote: > Hi Dan, > > On Fri, Sep 11, 2009 at 01:40:02PM -0400, Dan Pritts wrote: > > > > I'd say: Replace that USB 2.0 disk by something else like something > > > connected via Firewire or eSATA. USB 2.0 is very, very slow, especially > > > for random access. > > > > do you have empirical results that show this? > > I did not do benchmarks. It's just my personal experience that I've yet > to see an USB-attached disk which feels fast. Remember: Disks do not > speak USB, they are adressed via IDE or SATA. So, if you use USB, you > get an additional translation layer. > > Apart from that it looks like USB is not optimized for fast transfer and > low latency. SATA et al are designed for adressing hard disks, they > don't care about input devices etc. So there is less overhead. danno -- Dan Pritts, Sr. Systems Engineer Internet2 office: +1-734-352-4953 | mobile: +1-734-834-7224 Fall 2009 Internet2 Member Meeting, October 5-8 Hosted by the University of Texas at San Antonio and LEARN http://events.internet2.edu/2009/fall-mm/ ------------------------------------------------------------------------------ Come build with us! The BlackBerry® Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9-12, 2009. Register now! http://p.sf.net/sfu/devconf _______________________________________________ BackupPC-users mailing list BackupPC-users@lists.sourceforge.net List: https://lists.sourceforge.net/lists/listinfo/backuppc-users Wiki: http://backuppc.wiki.sourceforge.net Project: http://backuppc.sourceforge.net/