Visual Studio debugging painfully slow when loading symbols

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Mark Cassar

I have an issue which is practically similar to https://stackoverflow.com/questions/12567984/visual-studio-debugging-loading-very-slow but I haven't managed to find a solution to such a problem.

I have tried all what is described within that question and still, the symbol loading for the very first time is drastically slow.

Similarly to the other question, when starting an MVC project, I get several lines within the Output panel which consist of something similar to:

'iisexpress.exe' (Managed (v4.0.30319)): Loaded 'C:\Windows\Microsoft.NET\Framework\v4.0.30319\Temporary ASP.NET Files\root\02ba097f\ab73cbf7\App_Web__headerusermenu.cshtml.ee708ea.myhgafpb.dll', Symbols loaded.
'iisexpress.exe' (Managed (v4.0.30319)): Loaded 'C:\Windows\Microsoft.NET\Framework\v4.0.30319\Temporary ASP.NET Files\root\02ba097f\ab73cbf7\App_Web__layoutcmsbase.cshtml.ce72eb6d.ovoanhe-.dll', Symbols loaded.
'iisexpress.exe' (Managed (v4.0.30319)): Loaded 'C:\Windows\Microsoft.NET\Framework\v4.0.30319\Temporary ASP.NET Files\root\02ba097f\ab73cbf7\App_Web__notificationmessage.cshtml.5346933.9aei7ems.dll', Symbols loaded.

Such entries take around 300 - 500 ms each and these are executed for all the Partial Views we have within the project, which are quite considerable.

I have tried the solution within the other question but still didn't get any fast response times.

These are some tests we have made:

Using IIS Express

  • Loading website initially takes roughly 2 minutes
  • Stopping website and starting again takes around 1 min 45 sec
  • Once the website is running, I press on Load All Symbols (Tools > Otions > Debugging > Symbols > Load all symbols) and then stop project and run again, and it takes much less, round 25 sec. Still, the Load All Symbols button is disabled while the project isn't running, so for the very first time, I would need to wait until the project has loaded in order to press Load All Symbols

Using Visual Studio Development Server

  • Starting initially, takes roughly 50 sec
  • Stopped project and started again, takes roughly 20 sec
  • Clicking on Load All Symbols, stopping project and starting again takes roughly 15 sec

This is getting extremely frustrating as it is taking an extremely long amount of time in order to load project for the first time.

Any possible solution other than those mentioned within the question https://stackoverflow.com/questions/12567984/visual-studio-debugging-loading-very-slow which might help?

Try any of the following ...

  1. Enable Just My Code
    Go to Tools > Options > Debugging > General
    Check "Enable Just my Code"
    Enable Just my Code<br/><br/>

  2. Cache Symbols Locally
    Go to Tools > Options > Debugging > Symbols Browse to local directory (make sure it's not on a network share) Click "Load All Symbols" or run the project to hydrate the cache

    Cache Symbols<br/><br/>

  3. Remove Remote Symbol Servers

When you select a remote symbol server, Visual Studio gives you the following warning:

The performance of remote symbols stores can vary due to latency, bandwidth, or availability of servers. Debugging performance can be improved by selecting the option to load only specified modules when enabling this server

After loading your symbol cache, deselect remote symbols servers

Go to Tools > Options > Debugging > Symbols Deselect "Microsoft Symbol Servers" to prevent Visual Studio from remotely querying the Microsoft servers. Deselect Microsoft Symbol Servers

Further Reading

Stack Overflow

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