On 03/02/2011 08:09 PM, Bart Kus wrote: > Hello, > > I have the following setup: > > md_RAID6(10x2TB) -> LVM2 -> cryptsetup -> XFS > > When copying data onto the target XFS, I notice a large number of READs > occurring on the physical hard drives. Is there any way of monitoring > what might be causing these read ops? The blktrace command is extremely useful for this kind of I/O tracing. I've used it numerous times to figure out where I/O is originating and also how it's making its way through layers of stacked devices. There's a conference talk overview here from a few years ago: http://www.gelato.org/pdf/apr2006/gelato_ICE06apr_blktrace_brunelle_hp.pdf And also a user's guide: http://www.cse.unsw.edu.au/~aaronc/iosched/doc/blktrace.html http://pdfedit.petricek.net/bt/file_download.php?file_id=17&type=bug Regards, Bryn. _______________________________________________ linux-lvm mailing list linux-lvm@redhat.com https://www.redhat.com/mailman/listinfo/linux-lvm read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/
