Comment 3 for bug 1073956

After writing this I considered that availability-zone scheduling might just by pass scheduler logic since there is per force one choice.

I am definitely seeing this with the euca-run-instances -n case (I belive this is a single API request rather than the N api request the shell loop gives?).

Using the ChanceScheduler euca-run-instances -n 700 gives me 700 instance in active state in about 8min whit no over scheduling on compute nodes. I had about 800 unallocated VCPUs over 43 nodes when I ran this so it's a significant fraction of my available capacity.

Switching back to the FilterScheduler with the same command 230 instances got schedule on one node that only had 17 available.

I've seen similar behaviour with numbers as low as 100. (using packaged code not your patch)