We are writing the year 2012, and QEMU is still facing a challenge the Linux kernel already overcame: the BQL (Big QEMU Lock). This lock limits both scaling of userspace I/O paths and affects their latency, also preventing the use of QEMU for hard or even soft real-time workloads.
This talk will refresh the problem statement, analyze achievements of the last year and then look into current proposals to proceed with breaking the BQL. Aspects to be covered are
The presentation will be enriched with traps and pitfalls discovered via prototype implementations in the past year and shall trigger further discussions & ideas.