I've tested out a couple of ways of storing a queue structure and wondered if others had some better ideas. I tried a berkeleydb based queue using it's native queue structure, which gives the best performance so far but it's for unix only. I also have a file based queue where every message is just stored in a sequentially numbered file. Almost as fast as berkeleydb and works anywhere. Just for giggles I tried sqlite, and then immediately deleted it. 6-8 tps with sqlite compared to around 1000 with berkeleydb/flat files. Another alternative I was thinking of is a single file storage of some type, maybe fixed length or even variable length records. Something that's portable. But I'm thinking that could get complicated fairly quickly. Any other ideas?