You might consider PostgreSql too, although ten simple operations per second seems well within Mysql's capabililties unless your server is heavily loaded.

It is also possible that you could manage this size queue just fine either in memory, as a flat file perhaps using Tie::Array, or perhaps with a BerkelyDB (which excels as an object storage mechanism). How about just pushing onto / popping off of such a tied array, possibly with a Perl DB as object store?

Also, some basic code for a Queue is found in the book, Elements of Programming With Perl