How to determine total number of open/active connections in ms sql server 2005

Question

My PHP/MS Sql Server 2005/win 2003 Application occasionally becomes very unresponsive, the memory/cpu usage does not spike. If i try to open any new connection from sql man

Answer 1

I know this is old, but thought it would be a good idea to update. If an accurate count is needed, then column ECID should probably be filtered as well. A SPID with parallel threads can show up multiple times in sysprocesses and filtering ECID=0 will return the primary thread for each SPID.

SELECT 
    DB_NAME(dbid) as DBName, 
    COUNT(dbid) as NumberOfConnections,
    loginame as LoginName
FROM
    sys.sysprocesses with (nolock)
WHERE 
    dbid > 0
    and ecid=0
GROUP BY 
    dbid, loginame