This is what I got when done memory analysis of Dump of .Net server.

DotNetMemoryAnalysis
CLR Memory Analysis for UAE B2C WC REVAMP EXPRESS SEARCH LIVE-Memory-High-Dump-14-May.DMP

Type of Analysis Performed .Net Memory Pressure Analysis
Machine Name GCC-B2C-API-4
Operating System Windows Server – 20348
Number Of Processors 16
Process ID 9800
Process Image c:WindowsSystem32inetsrvw3wp.exe
Command Line c:windowssystem32inetsrvw3wp.exe -ap “UAE B2C WC REVAMP EXPRESS SEARCH LIVE” -v “v4.0” -l “webengine4.dll” -a .pipeiisipm8868b15b-43de-4c27-bab1-a056312fd59d -h “C:inetpubtempapppoolsUAE B2C WC REVAMP EXPRESS SEARCH LIVEUAE B2C WC REVAMP EXPRESS SEARCH LIVE.config” -w “” -m 0 -t 20 -ta 0
System Up-Time 27 day(s) 19:29:35
Process Up-Time 08:31:46
Processor Type X64
Process Bitness 64-Bit

CLR Information


 CLR version = 4.8.4645.0
 Microsoft.Diagnostics.Runtime version = 0.9.2.0

GC Root Chains

GC Root Chains are available for the following types:



|Type Name      |  Number of Roots Found  |Total Size|
|---------------|--------------------------|-----------|
|System.String   |   1555                |  178.31 KBytes |
|System.Char[]   | 8                    | 392 Bytes |
|System.String[] |               134     | 10.14 KBytes |
|System.Byte[]   |             189       | 799.17 KBytes |
|System.Int32[] |                 53    | 8.61 KBytes |
|System.DateTime  | 5                   | 120 Bytes |

Note: GC Root Chain detection is incomplete due to a timeout after 60 seconds. The GCRootTimeout and other settings can be modified in the DebugDiag.AnalysisRules.dll.config file.


**System.String**

**Type Name :**         System.String                
**Module Path:** C:WindowsMicrosoft.NetassemblyGAC_64mscorlibv4.0_4.0.0.0__b77a5c561934e089mscorlib.dll
 
**Total size of all instances:**
 
5.84 GBytes
 
**Number of instances:**

 30023662 

**Total size of all rooted instances:** 

178.31 KBytes 

**Number of rooted instances:** 

1555 


**Top GC Root Chains for System.String:**

**Total size of all objects with this GC Root Chain:**
88.44 KBytes 

**Number of objects with this GC Root Chain** 
1 

**Address of 1st object found with this GC Root Chain path***
 0x1b070b97568 


    static var System.Text.RegularExpressions.Regex.livecode-->
    System.Collections.Generic.LinkedList-->
    System.Collections.Generic.LinkedListNode-->
    System.Text.RegularExpressions.CachedCodeEntry-->
    System.Text.RegularExpressions.ExclusiveReference-->
    System.Text.RegularExpressions.RegexInterpreter-->
    System.String

Why System.String taking so much memory?