Hi all (especially Enis :) ), We are planning to use Amazon (Galaxy CloudMan) to run a workshop for about 50 people. We won't need to transfer any data during the workshop, but need the virtual cluster to be reasonably responsive and cope with: a) the load on the front end b) the workshop participants each trying to run a bwa alignment - at the moment each alignment would be of about 2.8M reads, but we could cut it down c) any other scalability issues I may not have thought of? I wanted to ask if anyone has used CloudMan for a similar purpose, or has an understanding, based on running a Galaxy cluster, of any problems we might encounter? I can add enough nodes to the cluster on the day to cope with the computational load (I assume) but I'm not sure if I should be expecting any other problems. Is the size of the node (e.g. Amazon's 4-core vs 8-core nodes) very important? I can scale out by adding more nodes, but should I be concerned about the capacity of the master node which handles the traffic? Also, is there any sensible way for me to test it in advance (in terms of the user load)? Many thanks for any advice! Clare -- E: sloc@unimelb.edu.au P: 03 903 53357 M: 0414 854 759