Concurrent Connection-ssas2005 RRS feed

  • Question

  • hi

    I have a ssas server on 64bit 4 cpu 16gb ram machine . Can anyone tell me how to find the max number of concurrent connections allowed to this server?  
    Any if only one user is connecting what is number of concurrent jobs he can run on the ssas server?


    Wednesday, December 15, 2010 5:44 PM


  • I don't believe that there is an enforced limit on the number of concurrent connections. I strongly suspect that the number of connections will be limited based more on available resources on the server before any artificial limit is enforced. As with all things you will need to test to see what you can get from your server based on your anticipated workload etc.

    In a test performed a long while back on AS2000 running on a 32 bit server and OS with the 3GB switch enabled we managed to get on the order of 244 connections executing representative queries where we hit just under the memory limit (i.e. 2.98Gb). On 64 bit servers with more memory clearly you can go well beyond this number but the workload of each query, concurrent processing and available threads and memory etc. will each take their toll on whether or not a new connection can be established and/or used.

    With regards "concurrent jobs", what do you mean by the term "job"? Essentially there are a number of finite resources that AS manages which includes process threads, query threads, jobs and memory etc. How this is managed is quite complex and I would suggest that you read the AS2005 Performance Guide for more information. (http://sqlcat.com/whitepapers/archive/2007/11/19/analysis-services-2005-performance-guide.aspx ) Essentially AS can perform tasks in parallel where a given task may well be a job. Within that job AS may determine that it can sub-divide that into other smaller jobs where each job will require a number of threads. The number of jobs that can be run in parallel and number of available threads are all configurable and impact the number of tasks/jobs etc. that can be executed in parallel and the point to which the server can become saturated.

    Note that even if you answer the question: "What is the maximum number of users that you expect to have running queries at any given moment" the point to which this is relevant is determined, amongst other things, by what each user is doing. Sometimes you may be able to have 300 users happily running queries but other times it may only be 10 due to the nature of the queries being executed etc.

    Wednesday, December 15, 2010 7:43 PM