--with-local-disks on 4.0 was buggy, that's why it was fast. (you could have block corruptions).
If this is slow, it's because it need to flush pending write before finish the migration. Depend of your storage speed, it can take some time.
(I have done test with ssd and 10gbe network, it take less than 1second)
If this is slow, it's because it need to flush pending write before finish the migration. Depend of your storage speed, it can take some time.
(I have done test with ssd and 10gbe network, it take less than 1second)