I took a dump of my process (w3wp) and opened it in WinDbg. I gave the following commands:
.loadby sos clr
!dumpheap -stat
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I then compared that to a snapshot taken in ANTS Memory Profiler 10:
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As you can see, the Symyx.Vault.Security.CachingExplicitPermissionService class is missing.
I then compared that to a snapshot taken in ANTS Memory Profiler 10:
As you can see, the Symyx.Vault.Security.CachingExplicitPermissionService class is missing.