On 13/04/2015 14:28, ein wrote: > > > Check out my update please: > http://lists.nongnu.org/archive/html/qemu-devel/2015-04/msg01318.html > > Using aio=native,cache=none results in 500%-2000% performance drop > comparing to bare metal and 300%-1000% comparing to > aio=threads,cache=unsafe.
Not a surprise that aio=threads,cache=unsafe is faster. With cache=unsafe you're telling QEMU that it's okay to lose data in case of a host power loss. Same for ext2 over XFS (ext2 isn't even journaled!). Thus, use XFS and preallocate storage using the "fallocate" command. Paolo
