11Feb/101
Restore from mysqldump --all-databases in parallel
csplit backup.sql /"^-- Current Database"/ {*}; for f in xx*; do cat xx00 "$f" | mysql& done;
and then rm xx* when the background jobs have finished.
I haven't done any benchmarking, and I haven't worked out what to do if the number of databases exceeds the number of available connections.