Theodore Ts'o <[email protected]> writes: > The current virtio block sets a queue depth of 64, which is > insufficient for very fast devices. It has been demonstrated that > with a high IOPS device, using a queue depth of 256 can double the > IOPS which can be sustained. > > As suggested by Venkatash Srinivas, set the queue depth by default to > be one half the the device's virtqueue, which is the maximum queue > depth that can be supported by the channel to the host OS (each I/O > request requires at least two VQ entries). > > Also allow the queue depth to be something which can be set at module > load time or via a kernel boot-time parameter, for > testing/benchmarking purposes.
Note that with indirect descriptors (which is supported by Almost Everyone), we can actually use the full index, so this value is a bit pessimistic. But it's OK as a starting point. Cheers, Rusty. _______________________________________________ Virtualization mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/virtualization
