I’ve made a post on StackOverflow – http://stackoverflow.com/questions/6718890/oracle-datareader-in-net-way-too-slow-over-network/6747497#6747497 about a weird performance issue Ive encountered with the 64 bit version of the Oracle Instant Client 11g. I’ve tested on other machines with a 32 bit client (though not instant) and it is much faster, around 10 times the speed, when using a simple datareader to fetch table records. The details are in that post, but I’ll just say that the performance was bad enough with this client that I had to seek an alternative to use for my project… and it wasn’t very pretty.
I’d be really curious to hear an explanation for this- plain ol bug, or is the supersized 64 bits causing the client to do extra work and killing the performance? Or is it just the instance client is always like this? The one thing I havent tried yet is using the 32 bit version of the instant client on the same machine and see if it improves things. I have a feeling it will…