The iSCSI driver used AIO, however it has been painful: - not rock solid - no unified event notification - no page-cache AIO support - no AIO FSYNC support The first issue is critical and the third and forth issues hurt scalability and performance, though we can live with the third one. I added new backing store code, bs_sync, which uses pthread and synchronous I/Os though I don't like to play with pthread. Now the iSCSI driver uses bs_sync code by default. Please test it. |