These problems typically come down to network latency and inter-machine communication. You'll need to make sure that your shared storage can perform well with random read and write operations:
Choosing a NAS device for ArcGIS Server—ArcGIS Server Administration (Windows) | ArcGIS Enterprise
A good tool for this is IOZone which can capture throughput of reading and writing to a certain directory:
On the ArcGIS Server machine, install the following software:
- IOZone (http://www.iozone.org/src/current/IozoneSetup.exe)
- cygwin (http://cygwin.com/setup-x86_64.exe)
*Note, there have been issues running IOZone with paths to the network from the machine the folder is shared to, meaning running IOZone from m1 to a share like \\m1\<path>
Sign in to the Server machine as the ArcGIS Server account and run the following command from the command line:
- "C:\Program Files (x86)\Benchmarks\Iozone3_414\iozone.exe" -Ra -f //networkpath/folder/file -b %USERPROFILE%\Desktop\networktest.xls
* Ideally, the //networkpath/file parameter would be set to the share to your server directories, for example //<machine>/arcgisserver/directories/file. In this directory, it'll create a simple file called "file" and run it's tests on that file.
If you have seen no problems with a server configured with local directories, run the following command as well when you're logged in with the ArcGIS Server account on that machine:
- "C:\Program Files (x86)\Benchmarks\Iozone3_414\iozone.exe" -Ra -f C:\arcgisserver\directories\file -b %USERPROFILE%\Desktop\localtest.xls
The parameters listed above are defined below:
-R = generates an Excel file
-a = uses full, automatic mode, meaning tests files with records sizes from 4k to 16M for file sizes 64K and 512M
-f = sets file path for output
-b = sets file path for Excel file.
If you're interested in knowing more about the tests that it will run, they can be read up on through the following pdf.
IoZone documentation:
http://www.iozone.org/docs/IOzone_msword_98.pdf
By taking ArcGIS Server out of the picture and comparing the results of simply reading and writing files to your shared location, you can determine if there's a networking problem to address.
The other thing to look at is if your site is configured to use a single cluster and if it's in single cluster mode.
About single cluster mode—ArcGIS Server Administration (Windows) | ArcGIS Enterprise
If this is an upgraded environment, you may have multiple clusters or single cluster mode may be disabled, which enables the communication between the machines that affects performance.