I'm having a lot of trouble getting throughput of mirrormaker to be consistent. On ec2, I have ~10 topics with pretty different throughputs, mirroring from 4 regions into 1. Total of about 20MBps. Sometimes it seems to be going fine, and then it seems like one of the consumers stops altogether, and restarting the process will let it catch back up. Sometimes I'll see errors in the logs about mirrormaker threads being stopped, and it doesn't seem like they ever get replaced.
Whats the recommended setup for mirrormaker? I've tried changing number of streams, producers, adding servers, splitting processes by topic or region, all to varying degrees of effect but still seem to just lose a partition periodically.