Fantastic article : couple of questions from someone spending a let of time reading perf-tools/performance counter outputs : 1 - "From looking at VTune profil

Fantastic article : couple of questions from someone spending a let of time reading perf-tools/performance counter outputs : 1 - "From looking at VTune profiling information, we saw that ISA-L was somehow reading both the source and destination buffers, rather than just writing to the destination buffer." This part intrigued me, i only have use VTUNE superficially, but how did you profile the destination addresses and correlate it to application level buffers? 2 - How are was it to profile kernel code, my experience is always hit and miss when using linux/perf-tool. 3 - A more general question, looking at the optimizations needed to saturate 100G NIC, it seems to me that you are guys are fundamentally approaching the scalability limits of the current IO/Networking model of current OS. How much do you think the current network stack can be squeeze (200G, 300G ?) before a complete redesign is necessary ? Is there any OS out there already design specifically for this kind of IO/Network performance (AIX,solaris maybe ?)