On 3/18/22 8:42 AM, Pavel Begunkov wrote: > On 3/18/22 13:52, Pavel Begunkov wrote: >> A WIP feature optimising out CQEs posting spinlocking for some use cases. >> For a more detailed description see 4/4. >> >> Quick benchmarking with fio/t/io_uring nops gives extra 4% to throughput for >> QD=1, and ~+2.5% for QD=4. > > Non-io_uring overhead (syscalls + userspace) takes ~60% of all execution > time, so the percentage should quite depend on the CPU and the kernel config. > Likely to be more than 4% for a faster setup. > > fwiw, was also usingIORING_ENTER_REGISTERED_RING, if it's not yet included > in the upstream version of the tool. But that seems to be exclusive of using PRIVATE_CQ? > Also, want to play after to see if we can also avoid taking uring_lock. That would certainly also be interesting! -- Jens Axboe
