Subject: Re: file system format for large, shared, removable USB disk
To: Steven M. Bellovin <firstname.lastname@example.org>
From: Charles M. Hannum <mycroft@MIT.EDU>
Date: 09/02/2006 16:11:09
On Sat, Sep 02, 2006 at 03:54:20PM -0400, Steven M. Bellovin wrote:
> On Sat, 2 Sep 2006 15:41:53 -0400, "Charles M. Hannum" <mycroft@MIT.EDU>
> > On Sat, Sep 02, 2006 at 02:34:56PM -0500, Michael Parson wrote:
> > > On Sat, Sep 02, 2006 at 03:26:41PM -0400, Steven M. Bellovin wrote:
> > > > I need to buy a large external hard drive that needs to work with both
> > > > NetBSD 3.0.1 and Linux, read-write. What are good choices for the file
> > > > system? Is our ext2 read-write support good enough? What is the largest
> > > > file system I can create that way?
> > >
> > > I've not tried ext2 under NetBSD, from what I've heard, it seems to do OK.
> > Unless clustering support has been added recently and I missed it, it
> > does *not* "do OK". The performance is worse than you can imagine.
> > (Ditto for msdosfs.)
> I knew that for msdosfs; that's one of the reasons I asked. Given the
> limits on our USB driver, though, it isn't clear to me that our ext2
> performance is the limiting factor...
I'm not sure about flash, but with disks I've found that the lack of
clustering is *much* worse with USB, probably because the turnaround to
get the next command out is long enough that we have a rotational delay.
I found msdosfs virtually unusable on a USB-connected drive.