Memory gates checking failed because the free memory (… 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.
If you look at the server into the Task Manager you will see that the noderunner.exe processes will consume a lot of memory. These processes run for the search.
To free some memory you can restart the process “SharePoint Search Host Controller”. Don’t be afraid when restarting take some time, couple of minutes. A lot of memory must be freed.
On our server we saw a 70% drop in memory usage. Configuring MMS was possible now.
Read Corey Roth’s blog for more indepth info about the various noderunner processes.