Concurrent queries in SQL Server 2005 Express

If applicable, what's the limit on concurrent queries supported by SQL Server 2005 Express? Also, if there's a limit, does next connection after the max errors out or merely queues up?

Thanks,

Phillip

hi Pjhillip,

PhillipM wrote:

If applicable, what's the limit on concurrent queries supported by SQL Server 2005 Express? Also, if there's a limit, does next connection after the max errors out or merely queues up?

Thanks,

Phillip

as in MSDE 2000 (and full blown SQL Server's editions), there's a "tecnical" limit of 32767 connections... and this can not be workarounded..

MSDE has another "limit", a built in Governer, but it does not prevent futher connections when the magic number of 8 concurrent workloads is reached.. it simply linearly slows down every I/O activity for all active connections...

SQLExpress does not include this query governor, but addresses the edition limitation reducing memory the process can address to 1gb (instead of 2gb for MSDE)...

this 1gb of memory includes all memory segments used by the server, so that data (and pages) cahed as long as query plans, memory structures for locks and additional providers are held within this "container"...
connections cost as well in term of memory strucures, so they are held within the very same limited "container"...

so, when no additional resources are available for the "next connection", the connecting process will hang up waiting for released resources... as soon as this task times out (connection timeout property), an exception will be raised...

regards

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Andrea,

Thanks a lot! I should extend my query timeout property then to be on the safe side.

Phillip