MDS error: HttpWebRequest WebException RemoteServer : Arguments:NotFound.

[Peter Schmitz]

Today, we ran into an issue when attempting to connect to MDS on our production server. MDS itself opened up fine, but when clicking on "Explorer", we were greeted with an ugly error message:

The error message conveniently cannot be copied/pasted.

As it turns out, this error was caused by our production server passing a memory threshold, causing MDS not to properly load. To troubleshoot this, we directly connected to the MDS service endpoint powering MDS (i.e. http://<servername>/MDS/service/Service.svc?SingleWSDL).

There, we were greeted with the following error:

Server Error in '/MDS' Application.

Memory gates checking failed because the free memory (972304384 bytes) is less than 5% of total memory. As a result, the service will not be available for incoming requests. To resolve this, either reduce the load on the machine or adjust the value of minFreeMemoryPercentageToActivateService on the serviceHostingEnvironment config element.

We resolved the issue by reducing the max memory setting of SQL Server. This was done by using the following command :

EXEC sys.sp_configure N'max server memory (MB)', N'45000' -- was 50000
GO
RECONFIGURE WITH OVERRIDE
GO

Changing this setting takes effect immediately, and does NOT require a reboot.