On Thu, Nov 16, 2017 at 03:51:29PM +0100, Peter Lieven wrote: > Afaik all writes to the same QCOW2 serialize because of the s->lock that > is held during the write. So its not suprising that there is no benefit from > mutliple threads as long as reading from the RAW file involves no delay. > Which is likely due to readahead of the OS.
I guess this would explain it, thanks. Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com virt-df lists disk usage of guests without needing to install any software inside the virtual machine. Supports Linux and Windows. http://people.redhat.com/~rjones/virt-df/