Slow Request

Check application insights to find more details about the slowness

Drill into samples

If we don't see any slow dependency, that means the time is spent inside the code

If the issue is reproducible on demand you can Collect profiler trace :

Or you can use auto heal to collect profiler trace or memory dump by creating a rule for slowness

Use AutoHeal to collect Memory Dump or Profiler Trace

Or you can use auto heal to collect profiler trace or memory dump by creating a rule for slowness

Once we have collected the memory dump using SlowPage scenario

https://buggyappservice.azurewebsites.net/SlowPage/Index/time=40000

Open Memory dump in WinDbg

First thing we always check in the dump is the CLR version and establish if we are in a supported scenario.

lmvm clr .net framework

lmvm coreclr .net core

Checking running requests:

!aspxcorepages -n -a

!ck2

!decompilemember BuggyAppService!BuggyAppService.Controllers.SlowPage.Index

We can see that thread 34 stack, specifically BuggyAppService!BuggyAppService.Controllers.SlowPage.Index calls Thread.Sleep().