Tomcat 7 represents a bottleneck for Alfresco Platform in a headless usecase, in order to resolve this issue the best solution is to move to support Tomcat 8
This issue surfaced from the 1billion benchmarking initiative.
In situations where an Alfresco cluster is subjected to a high number of CMIS concurrent sessions Tomcat 7 acts as a rate limiter and provides an artificial blocker to restrict the performance Alfresco is capable of for a given server specification.
This ticket is to move to supporting Tomcat 8 from Tomcat 7 in the next appropriate release to support these high-volume use-cases.
The rate limiting of Tomcat 7 for CMIS can be sidestepped by scaling out to additional nodes to achieve more throughput.
Caution: This however would mean the servers are being under utilised and result in additional node costs for customers driven not by Alfresco performance, but by our dependency on Tomcat 7.