It is running on a P3 machine with 1G RAM (I forgot the speed). The box is dedicated for MySQL server, so it's got all the resources to itself.

Yes it is a hotel reservation system. It has a fairly complex rules to search for availability. Rooms have maximum capacity. Packages have minimum and maximum number of guests, there are also different special packages for valued guests, travel agents, online marketing referrals. Prices can have seasons and each season can have different prices for different room-package combination. There are more rules.

Searching for availability must consider those variables. The results from these computation for a given date is stored in a so-called 'search cache', so the next search on the date don't need to do the computation again. The problem with this is that all search use this table, so it is havily read, but if its data isn't valid, it is updated/inserted, which makes it havily written as well.

I am looking for suggestion to improve performance for a real time system like this and to hear what other monks think about my approach on the problem. Thanks a lot for reply.