How to prevent proxy timeouts with SQL Server Reporting Services

Question

We have a system running Windows Server 2008R2 x64 and SQL Server 2008R2 x64 with SSRS installed/configured. This is a shared reporting server used by a large number of people, with some fairly large inefficient databases (400-500gb of data ish), and these users use the system to generate ad-hoc reports based of a reporting model that sits on top of the aforementioned databases. Note that the users are using NTLM to logon and identify for running reports.

Most reports are quick, but if you are running a report for 1 or 2 years worth of data, they can take a while to return (5minutes ish). This is fine for most users, however some of the users are stuck behind a proxy, which has a connection timeout set at 2minutes. As SSRS 2008R2 does not seem to send back a "keep-alive" signal (confirmed via wireshark), when running one of these long reports the proxy server thinks the connection has died, and as such it just gives up and kills the connection. This gives the user a 401 or 503 error and obviously cancels the report (the incorrect error is a known bug in SSRS which Microsoft refuse to fix).

We're getting a lot of flak from the user's about this, even though it's not really our issue..so I am looking for a creative solution.

So far I have come up with:

1) Discovering some as yet unknown setting for SSRS that can make it keep the connection alive.
2) installing our own proxy in between the users and our reports server, which WILL send a keep-alive back (not sure this will work and it's a bit hacky, just thinking creatively!)
3) re-writing our reports databases to be more efficient (yes this is the best solution, but also incredibly expensive)
4) ask the experts :) :)

We have a call booked in with Microsoft Support to see if they can help - but can any experts on Stack help out? I appreciate that this may be a better question for server fault (and I may post it there) but it's a development question too really :)

Thanks!

Answer 1

A few things:

A. For SSRS overall on it's service:

I personally use a keep alive service as I believe the default recycle is 12 hours for SSRS server. I use a tool someone turned me onto called 'VisualCron' that can do many task processes automatically. You can also just make a call in a WCF service or similar to. Basically I know the first report from a user for the day is generally slow. Usually you need to hit http:// (servername)/ReportServer to keep it alive.

B. For cachine report level items:

If this does not help I would suggest possibly caching DataSets when possible. Some people have data that is up to the moment but for a lot of people that is not the case. You may create a shared dataset in SSRS and then cache that on a schedule. So if you have domain like tables that only need to be updated once in a blue moon put them there. Same with data that is nightly or in batches. If you are transactional based shop that is up to the moment this may not help but for batch based businesses this can help tremendously.

You can also cache the reports for their data as a continuation of this. Under 'Manage' drop down for a report when in the /Reports landing page you can set the data to run under a specific schedule. You can also set a snapshot which is an extension of this as it executes with some default parameters set on a schedule and is a copy of the report when it was ran.

You are mentioning ASP.NET so I am not certain how much some of this will work if you are doing this all through a site you are setting up internally as a pass through. But you could email or save files on a schedule as well through SSRS's subscription service.

C. Change how you store your data for reporting.

You can create a Report Warehouse of select item level values of queries. Create a small database that is just a few recent years of data and only certain fields and certain tables. Then index it to death and report off of that. In my experience this method will fly in terms of performance but it does take the extra overhead of setting it up. Generally most companies will whine about this but it often takes a single day to set up and then you create one SSMS job that does it all nightly or an SSIS package then you don't worry about it. I like this method as I know my data is not being reported off of production and is isolated personally.