[ovirt-users] VM resource allocation and IO Threads

Hello, can anyone give any pointer to deeper information about what in subject and the value for "Num Of IO Threads" configuration, best practices and to-be-expected improvements? I read also here: https://access.redhat.com/documentation/en-us/red_hat_virtualization/4.1/... but in some points it seems not so clear to me: eg: If a virtual machine has more than one disk, you can enable or change the number of IO threads to improve performance. but also Red Hat recommends using the default number of IO threads, which is 1. There is also a note about deactivation and activation of disks: does it mean that even if I poweroff the VM and change its config I have to make this step after? Anyone has run benchmarks? Does it make sense if my VM has 3 disks to configure 6 IO threads for example? Do IO threads map to SCSI controllers inside the guest or what? Thanks in advance, Gianluca