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rhamlett_microsoft
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Updated documentation, added Procdump info, cleaned up code block displays
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‎.vscode/launch.json‎

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{
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"version": "0.2.0",
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"configurations": [
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{
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"name": "Launch PerfProblemSimulator",
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"type": "coreclr",
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"request": "launch",
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"preLaunchTask": "build",
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"program": "${workspaceFolder}/src/PerfProblemSimulator/bin/Debug/net10.0/PerfProblemSimulator.dll",
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"args": [],
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"cwd": "${workspaceFolder}/src/PerfProblemSimulator",
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"stopAtEntry": false,
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"serverReadyAction": {
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"action": "openExternally",
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"pattern": "\\bNow listening on:\\s+(https?://\\S+)"
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},
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"env": {
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"ASPNETCORE_ENVIRONMENT": "Development"
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}
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}
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]
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}

‎.vscode/tasks.json‎

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{
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"version": "2.0.0",
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"tasks": [
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{
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"label": "build",
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"command": "dotnet",
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"type": "process",
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"args": [
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"build",
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"${workspaceFolder}/src/PerfProblemSimulator/PerfProblemSimulator.csproj",
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"/property:GenerateFullPaths=true",
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"/consoleloggerparameters:NoSummary;ForceNoAlign"
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],
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"problemMatcher": "$msCompile"
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},
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{
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"label": "watch",
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"command": "dotnet",
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"type": "process",
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"args": [
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"watch",
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"run",
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"--project",
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"${workspaceFolder}/src/PerfProblemSimulator/PerfProblemSimulator.csproj"
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],
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"problemMatcher": "$msCompile"
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}
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]
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}

‎docs/azure-monitoring-guide.md‎

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---
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## 💥 Diagnosing Application Crashes
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### Symptoms
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- Application suddenly becomes unavailable
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- HTTP 502/503 errors returned to clients
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- Azure auto-restarts the application
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- Event logs show process termination
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### Azure Crash Monitoring
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Azure App Service includes built-in Crash Monitoring that can automatically capture memory dumps when your application crashes.
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#### Enabling Crash Monitoring
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1. Navigate to your App Service in the Azure Portal
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2. Go to **Diagnose and solve problems**
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3. Search for "Crash Monitoring"
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4. Enable crash dump collection
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> **⚠️ Important: Storage Account Restrictions**
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>
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> In some Azure environments, Crash Monitoring may not work due to security restrictions on storage accounts. If you cannot use Crash Monitoring, you can collect memory dumps manually using **ProcDump** from the Kudu console.
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### Using ProcDump for Manual Dump Collection
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[ProcDump](https://learn.microsoft.com/en-us/sysinternals/downloads/procdump) is a Sysinternals command-line utility that can monitor applications and generate crash dumps. It's available on Azure App Service through the Kudu console.
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#### Accessing the Kudu Console
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1. Navigate to your App Service
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2. Go to **Development Tools** > **Advanced Tools**
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3. Click **Go** to open Kudu
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4. Select **Debug console** > **CMD** or **PowerShell**
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#### Common ProcDump Commands
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```bash
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# Write a full memory dump of a process by name
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procdump -ma w3wp.exe
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# Write a full dump when an unhandled exception occurs
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procdump -ma -e w3wp.exe
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# Write a full dump on 1st or 2nd chance exception
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procdump -ma -e 1 w3wp.exe
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# Write up to 10 dumps, one per exception
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procdump -ma -n 10 -e 1 w3wp.exe
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# Write a dump when CPU exceeds 80% for 10 seconds
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procdump -ma -c 80 -s 10 w3wp.exe
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# Write a dump when memory exceeds 1GB
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procdump -ma -m 1024 w3wp.exe
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# Write a dump when a hung window is detected
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procdump -ma -h w3wp.exe
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```
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#### ProcDump Options Reference
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| Option | Description |
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|--------|-------------|
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| `-ma` | Full dump (all memory) |
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| `-mm` | Mini dump (default, smaller size) |
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| `-mp` | MiniPlus dump (detailed but 10-75% smaller than full) |
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| `-e` | Dump on unhandled exception (add `1` for first-chance) |
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| `-c` | CPU threshold percentage |
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| `-m` | Memory commit threshold in MB |
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| `-n` | Number of dumps to write before exiting |
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| `-s` | Consecutive seconds before dump (default 10) |
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| `-h` | Dump on hung window |
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| `-t` | Dump on process termination |
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#### Downloading the Dump File
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1. In Kudu, navigate to the folder where the dump was created
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2. Click the download icon next to the `.dmp` file
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3. Open the dump in Visual Studio, WinDbg, or another debugger
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---
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## ⏱️ Using the Request Latency Monitor
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The dashboard includes a **Request Latency Monitor** that demonstrates how thread pool starvation affects request processing time.

‎src/PerfProblemSimulator/wwwroot/azure-monitoring-guide.html‎

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font-family: 'Cascadia Code', 'Consolas', monospace;
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font-size: 0.875rem;
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line-height: 1.6;
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white-space: pre;
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}
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.code-block .comment { color: #6a9955; }
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<li><a href="#cpu">Diagnosing High CPU</a></li>
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<li><a href="#memory">Diagnosing Memory Pressure</a></li>
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<li><a href="#threads">Diagnosing Thread Pool Starvation</a></li>
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<li><a href="#crash">Diagnosing Application Crashes</a></li>
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<li><a href="#latency">Latency Monitor</a></li>
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<li><a href="#setup">Monitoring Setup</a></li>
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<li><a href="#best-practices">Best Practices</a></li>
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</div>
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</section>
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<!-- Diagnosing Application Crashes Section -->
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<section id="crash" class="doc-section">
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<h2>💥 Diagnosing Application Crashes</h2>
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<h3>Symptoms</h3>
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<ul>
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<li>Application suddenly becomes unavailable</li>
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<li>HTTP 502/503 errors returned to clients</li>
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<li>Azure auto-restarts the application</li>
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<li>Event logs show process termination</li>
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</ul>
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<h3>Azure Crash Monitoring</h3>
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<p>Azure App Service includes built-in Crash Monitoring that can automatically capture memory dumps when your application crashes.</p>
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<h4>Enabling Crash Monitoring</h4>
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<ol>
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<li>Navigate to your App Service in the Azure Portal</li>
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<li>Go to <strong>Diagnose and solve problems</strong></li>
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<li>Search for "Crash Monitoring"</li>
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<li>Enable crash dump collection</li>
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</ol>
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<div class="info-box">
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<h4>⚠️ Important: Storage Account Restrictions</h4>
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<p>In some Azure environments, Crash Monitoring may not work due to security restrictions on storage accounts. If you cannot use Crash Monitoring, you can collect memory dumps manually using <strong>ProcDump</strong> from the Kudu console.</p>
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</div>
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<h3>Using ProcDump for Manual Dump Collection</h3>
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<p><a href="https://learn.microsoft.com/en-us/sysinternals/downloads/procdump" target="_blank">ProcDump</a> is a Sysinternals command-line utility that can monitor applications and generate crash dumps. It's available on Azure App Service through the Kudu console.</p>
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<h4>Accessing the Kudu Console</h4>
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<ol>
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<li>Navigate to your App Service</li>
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<li>Go to <strong>Development Tools</strong> &gt; <strong>Advanced Tools</strong></li>
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<li>Click <strong>Go</strong> to open Kudu</li>
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<li>Select <strong>Debug console</strong> &gt; <strong>CMD</strong> or <strong>PowerShell</strong></li>
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</ol>
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<h4>Common ProcDump Commands</h4>
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<div class="code-block">
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<span class="comment"># Write a full memory dump of a process by name</span>
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procdump -ma w3wp.exe
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<span class="comment"># Write a full dump when an unhandled exception occurs</span>
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procdump -ma -e w3wp.exe
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<span class="comment"># Write a full dump on 1st or 2nd chance exception</span>
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procdump -ma -e 1 w3wp.exe
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<span class="comment"># Write up to 10 dumps, one per exception</span>
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procdump -ma -n 10 -e 1 w3wp.exe
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<span class="comment"># Write a dump when CPU exceeds 80% for 10 seconds</span>
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procdump -ma -c 80 -s 10 w3wp.exe
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<span class="comment"># Write a dump when memory exceeds 1GB</span>
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procdump -ma -m 1024 w3wp.exe
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<span class="comment"># Write a dump when a hung window is detected</span>
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procdump -ma -h w3wp.exe
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</div>
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<h4>ProcDump Options Reference</h4>
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<table class="latency-table">
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<thead>
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<tr>
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<th>Option</th>
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<th>Description</th>
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</tr>
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</thead>
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<tbody>
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<tr>
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<td><code>-ma</code></td>
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<td>Full dump (all memory)</td>
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</tr>
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<tr>
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<td><code>-mm</code></td>
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<td>Mini dump (default, smaller size)</td>
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</tr>
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<tr>
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<td><code>-mp</code></td>
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<td>MiniPlus dump (detailed but 10-75% smaller than full)</td>
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</tr>
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<tr>
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<td><code>-e</code></td>
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<td>Dump on unhandled exception (add <code>1</code> for first-chance)</td>
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</tr>
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<tr>
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<td><code>-c</code></td>
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<td>CPU threshold percentage</td>
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</tr>
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<tr>
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<td><code>-m</code></td>
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<td>Memory commit threshold in MB</td>
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</tr>
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<tr>
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<td><code>-n</code></td>
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<td>Number of dumps to write before exiting</td>
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</tr>
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<tr>
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<td><code>-s</code></td>
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<td>Consecutive seconds before dump (default 10)</td>
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</tr>
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<tr>
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<td><code>-h</code></td>
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<td>Dump on hung window</td>
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</tr>
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<tr>
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<td><code>-t</code></td>
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<td>Dump on process termination</td>
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</tr>
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</tbody>
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</table>
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<h4>Downloading the Dump File</h4>
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<ol>
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<li>In Kudu, navigate to the folder where the dump was created</li>
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<li>Click the download icon next to the <code>.dmp</code> file</li>
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<li>Open the dump in Visual Studio, WinDbg, or another debugger</li>
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</ol>
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</section>
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<!-- Using the Request Latency Monitor Section -->
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<section id="latency" class="doc-section">
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<h2>⏱️ Using the Request Latency Monitor</h2>

‎src/PerfProblemSimulator/wwwroot/documentation.html‎

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font-family: 'Cascadia Code', 'Consolas', monospace;
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font-size: 0.875rem;
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line-height: 1.6;
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white-space: pre;
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}
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.code-block .comment { color: #6a9955; }

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