Windows 2012R2, WT

With an insert-only workload, using the bulk-insert api provides a ~2x improvement in throughput. Using the same test as SERVER-26753, but simply using a bulk-insert of 10 documents (whereas the original test inserted 1), the overall steady-state performance is marginally improved (~3%) but the cpu usage goes from ~55% to 100%.

I realize we are asking more of the DB, but I'm surprised at how little of an improvement there is given the significant increase in CPU usage. Is it possible there is a significant amount of time spent spinning?

Please see the attached diagnostics.