MSDE Scalability

Ever wanted the definitive answer on just exactly how MSDE limits performance and scalability? Well, you’re in luck, as Microsoft has now published a whitepaper describing how the governor in MSDE works. The short version is that the governor stalls connections for a few milliseconds on each logical read or write, once the limit of more than eight concurrent operations has been reached. The connection limit for MSDE is the same as for a standard SQL Server instance (32,767), but obviously the more concurrent connections, the more likely you are to reach the limit of 8 concurrent operations that triggers the workload governor. Read the paper for all the juicy details, including specifics on physical vs. logical reads/writes, and how/when the governor is activated. Good stuff.

[via the VSDATA Team blog]

UPDATE: It looks like the original link is no longer valid. I'm not sure if it's exactly the same whitepaper, but another discussion of the MSDE 2000 workload governor can be found here.