{"id":54158,"date":"2025-11-25T04:02:27","date_gmt":"2025-11-25T04:02:27","guid":{"rendered":"https:\/\/www.devopsschool.com\/blog\/?p=54158"},"modified":"2025-11-25T04:02:27","modified_gmt":"2025-11-25T04:02:27","slug":"dotnet-counters-commands-and-metrcies","status":"publish","type":"post","link":"https:\/\/www.devopsschool.com\/blog\/dotnet-counters-commands-and-metrcies\/","title":{"rendered":"dotnet-counters: commands and Metrcies"},"content":{"rendered":"\n

<\/p>\n\n\n\n

\n\n\n\n

\u2705 dotnet-counters \u2013 Command Reference (Explained Simply)<\/strong><\/h1>\n\n\n\n

When you run:<\/p>\n\n\n

dotnet-counters -h\n<\/code><\/span><\/pre>\n\n\n
You see 4 main commands:<\/p>\n\n\n
Commands<\/span>:\n  monitor<\/span>   Start<\/span> monitoring<\/span> a<\/span> .NET<\/span> application<\/span>\n  collect<\/span>   Monitor<\/span> counters<\/span> in<\/span> a<\/span> .NET<\/span> application<\/span> and<\/span> export<\/span> the<\/span> result<\/span> into<\/span> a<\/span> file<\/span>\n  list<\/span>      Display<\/span> a<\/span> list<\/span> of<\/span> counter<\/span> names<\/span> and<\/span> descriptions<\/span>, grouped<\/span> by<\/span> provider<\/span>.\n  ps<\/span>        Lists<\/span> the<\/span> dotnet<\/span> processes<\/span> that<\/span> can<\/span> be<\/span> monitored<\/span>.\n<\/code><\/span>Code language:<\/span> CSS<\/span> (<\/span>css<\/span>)<\/span><\/small><\/pre>\n\n\n
Below is a simple explanation for each<\/strong>.<\/p>\n\n\n\n
\n\n\n\n
\ud83d\udfe6 1. dotnet-counters monitor<\/strong><\/h1>\n\n\n\n
Real-time monitoring (LIVE metrics)<\/strong><\/h3>\n\n\n\n
This command shows metrics live in the terminal<\/strong>.<\/p>\n\n\n\n
Example:<\/p>\n\n\n
dotnet-counters<\/span> monitor<\/span> --process-id<\/span> 1234 System<\/span>.Runtime<\/span> Microsoft<\/span>.AspNetCore<\/span>.Hosting<\/span>\n<\/code><\/span>Code language:<\/span> CSS<\/span> (<\/span>css<\/span>)<\/span><\/small><\/pre>\n\n\n
Use when:<\/p>\n\n\n\n
    \n
  • You want to diagnose CPU spikes<\/li>\n\n\n\n
  • You want to monitor GC, ThreadPool, HTTP requests, EF load<\/li>\n\n\n\n
  • You need instant<\/strong> insights<\/li>\n<\/ul>\n\n\n\n
    \n\n\n\n
    \ud83d\udfe7 2. dotnet-counters collect<\/strong><\/h1>\n\n\n\n
    Record metrics into a file<\/strong> (for later analysis)<\/h3>\n\n\n\n
    Example:<\/p>\n\n\n
    dotnet-counters<\/span> collect<\/span> --process-id<\/span> 1234 -o<\/span> metrics<\/span>.json<\/span>\n<\/code><\/span>Code language:<\/span> CSS<\/span> (<\/span>css<\/span>)<\/span><\/small><\/pre>\n\n\n
    Use when:<\/p>\n\n\n\n
      \n
    • You want offline analysis<\/li>\n\n\n\n
    • You want to attach the file to Jira\/Slack<\/li>\n\n\n\n
    • You want long-running capture for production<\/li>\n<\/ul>\n\n\n\n
      The output can be consumed by:<\/p>\n\n\n\n
        \n
      • PerfView<\/li>\n\n\n\n
      • VS Diagnostic tools<\/li>\n\n\n\n
      • Custom dashboards<\/li>\n<\/ul>\n\n\n\n
        \n\n\n\n
        \ud83d\udfe9 3. dotnet-counters list<\/strong><\/h1>\n\n\n\n
        Lists ALL available counters grouped by provider<\/strong><\/h3>\n\n\n\n
        Example:<\/p>\n\n\n
        dotnet-counters list<\/span>\n<\/code><\/span>Code language:<\/span> PHP<\/span> (<\/span>php<\/span>)<\/span><\/small><\/pre>\n\n\n
        It shows providers such as:<\/p>\n\n\n\n
          \n
        • System.Runtime<\/code><\/li>\n\n\n\n
        • Microsoft.AspNetCore.Hosting<\/code><\/li>\n\n\n\n
        • Microsoft.EntityFrameworkCore<\/code><\/li>\n\n\n\n
        • Microsoft.AspNetCore.Http.Connections<\/code><\/li>\n\n\n\n
        • Grpc.AspNetCore.Server<\/code><\/li>\n\n\n\n
        • Custom counters you create<\/li>\n<\/ul>\n\n\n\n
          Use when:<\/p>\n\n\n\n
            \n
          • You want to know which counters exist<\/li>\n\n\n\n
          • You want to pick the right providers for monitoring<\/li>\n<\/ul>\n\n\n\n
            \n\n\n\n
            \ud83d\udfea 4. dotnet-counters ps<\/strong><\/h1>\n\n\n\n
            Shows all .NET processes which can be monitored<\/strong><\/h3>\n\n\n\n
            Example:<\/p>\n\n\n
            dotnet-counters ps\n<\/code><\/span><\/pre>\n\n\n
            Output:<\/p>\n\n\n
            1234  Orders<\/span>.Api<\/span>\n5678  WorkerService1<\/span>\n<\/code><\/span>Code language:<\/span> CSS<\/span> (<\/span>css<\/span>)<\/span><\/small><\/pre>\n\n\n
            Use when:<\/p>\n\n\n\n
              \n
            • You don\u2019t know the PID<\/li>\n\n\n\n
            • You want to confirm your app is running<\/li>\n\n\n\n
            • You want to attach to the correct process<\/li>\n<\/ul>\n\n\n\n
              \n\n\n\n
              \ud83d\udcdd Slide-Ready Summary<\/strong><\/h1>\n\n\n\n
              dotnet-counters \u2013 Core Commands<\/strong><\/h2>\n\n\n\n
              Command<\/th>What It Does<\/th>When to Use<\/th><\/tr><\/thead>
              monitor<\/strong><\/td>Shows live runtime metrics<\/strong> in console<\/td>Realtime troubleshooting<\/td><\/tr>
              collect<\/strong><\/td>Records metrics to a file<\/strong><\/td>Post-analysis \/ long runs<\/td><\/tr>
              list<\/strong><\/td>Shows all available counters<\/td>Discover providers\/counters<\/td><\/tr>
              ps<\/strong><\/td>Lists .NET processes<\/td>To find PID to attach<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
              \n\n\n\n
              <\/p>\n\n\n\n
              \n\n\n\n
              Master Table: Important dotnet-counters Metrics (with Explanations & Why They Matter)<\/strong><\/h1>\n\n\n\n
              \n\n\n\n
              1\ufe0f\u20e3 System.Runtime \u2014 Core CLR Runtime Metrics<\/strong><\/h1>\n\n\n\n
              Metric<\/th>What It Means<\/th>Why It\u2019s Important for Performance<\/th><\/tr><\/thead>
              CPU Usage (%)<\/strong><\/td>CPU percentage used by the .NET process<\/td>Detects CPU bottlenecks; helps identify CPU-bound workloads, infinite loops, bad parallelism, or excessive processing.<\/td><\/tr>
              Allocation Rate (B\/sec)<\/strong><\/td>How fast your app allocates managed memory<\/td>High allocation rate \u2192 frequent GC \u2192 latency spikes. Crucial for diagnosing app churn, LINQ inefficiencies, and memory-heavy code.<\/td><\/tr>
              GC Heap Size (MB)<\/strong><\/td>Total memory currently used by the managed heap<\/td>Detects memory leaks, memory growth over time, and inefficient caching patterns.<\/td><\/tr>
              GC Committed Bytes (MB)<\/strong><\/td>Memory reserved by GC from OS<\/td>Helps understand total memory pressure; correlates with working set expansion.<\/td><\/tr>
              % Time in GC<\/strong><\/td>Percentage of time spent in garbage collection<\/td>High value = app is frequently pausing; leads to latency issues and poor throughput.<\/td><\/tr>
              Time paused by GC (ms\/sec)<\/strong><\/td>Actual stop-the-world pause time<\/td>High pause time directly causes slow API responses and jitter.<\/td><\/tr>
              Gen 0\/1\/2 GC Count<\/strong><\/td>Number of collections happening per second<\/td>High Gen0 = object churn. High Gen2 = severe performance issue because Gen2 GCs are expensive.<\/td><\/tr>
              Gen 0\/1\/2 Size<\/strong><\/td>Total bytes in each generation<\/td>Helps identify long-lived allocations, memory retention, and leaks.<\/td><\/tr>
              LOH Size (Large Object Heap)<\/strong><\/td>Memory used by objects \u226585 KB<\/td>LOH fragments memory; too big LOH increases GC cost. Critical for APIs that allocate large arrays\/JSON blobs.<\/td><\/tr>
              POH Size (Pinned Object Heap)<\/strong><\/td>Memory that GC cannot move<\/td>High POH = higher fragmentation + potential leaks. Important for interop-heavy systems.<\/td><\/tr>
              ThreadPool Thread Count<\/strong><\/td>Number of active worker threads<\/td>Too low \u2192 starvation. Too high \u2192 excessive context switching.<\/td><\/tr>
              ThreadPool Queue Length<\/strong><\/td>Work items waiting for a thread<\/td>If >0 consistently \u2192 request queuing \u2192 latency spikes.<\/td><\/tr>
              ThreadPool Completed Work Items\/sec<\/strong><\/td>Work throughput<\/td>Helps measure workload intensity and server utilization.<\/td><\/tr>
              Lock Contention Count\/sec<\/strong><\/td>Threads waiting to enter locks<\/td>Indicates concurrency bottlenecks causing hangs and slowdowns.<\/td><\/tr>
              Exception Count\/sec<\/strong><\/td>Exceptions thrown each second<\/td>High exceptions degrade performance due to stack walking + GC pressure.<\/td><\/tr>
              Working Set (MB)<\/strong><\/td>Total memory used by the process<\/td>High working set may cause swapping or OOM kills in containers.<\/td><\/tr>
              IL Bytes Jitted \/ Methods Jitted<\/strong><\/td>Total methods compiled by JIT<\/td>High values over time = JIT warmup not complete; affects startup latency.<\/td><\/tr>
              Active Timers<\/strong><\/td>Number of active timer callbacks<\/td>Too many timers \u2192 excessive scheduling overhead.<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
              \n\n\n\n
              2\ufe0f\u20e3 Microsoft.AspNetCore.Hosting \u2014 Request & Application Metrics<\/strong><\/h1>\n\n\n\n
              Metric<\/th>What It Means<\/th>Why It Matters<\/th><\/tr><\/thead>
              Requests\/sec<\/strong><\/td>Incoming requests throughput<\/td>Measures system load; used to detect saturation and capacity.<\/td><\/tr>
              Current Requests<\/strong><\/td>In-flight HTTP requests<\/td>High values = backpressure or slow request handlers.<\/td><\/tr>
              Total Requests<\/strong><\/td>Cumulative number of served requests<\/td>Useful for verifying app activity during load tests.<\/td><\/tr>
              Failed Requests<\/strong><\/td>Number of failed requests<\/td>Identifies reliability\/stability issues.<\/td><\/tr>
              Request Queue Length<\/strong><\/td>Pending incoming requests<\/td>Queue > 0 \u2192 server not keeping up \u2192 potential cascading failure.<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
              \n\n\n\n
              3\ufe0f\u20e3 Microsoft-AspNetCore-Server-Kestrel \u2014 Server-Level Metrics<\/strong><\/h1>\n\n\n\n
              Metric<\/th>Meaning<\/th>Why It Matters<\/th><\/tr><\/thead>
              Current Connections<\/strong><\/td>Active TCP connections<\/td>Detects overload, DDoS-like patterns, or connection leaks.<\/td><\/tr>
              Connection Queue Length<\/strong><\/td>Pending connections before they\u2019re accepted<\/td>High queue = server saturation.<\/td><\/tr>
              TLS Handshake Failures<\/strong><\/td>Failed SSL handshakes<\/td>Indicates certificate issues or client misconfigurations.<\/td><\/tr>
              Request Queue Length<\/strong><\/td>HTTP requests waiting to be processed<\/td>Early warning sign of API latency under load.<\/td><\/tr>
              Connections\/sec<\/strong><\/td>New incoming connections\/second<\/td>High churn can cause CPU spikes and port exhaustion.<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
              \n\n\n\n
              4\ufe0f\u20e3 Microsoft.AspNetCore.Http.Connections \u2014 SignalR & WebSockets<\/strong><\/h1>\n\n\n\n
              Metric<\/th>Meaning<\/th>Why It Matters<\/th><\/tr><\/thead>
              Current Connections<\/strong><\/td>Active WebSocket\/SignalR connections<\/td>Helps size the real-time workload.<\/td><\/tr>
              Connections Started<\/strong><\/td>New connections opened<\/td>High rate = scaling pressure on real-time hubs.<\/td><\/tr>
              Connections Stopped<\/strong><\/td>Closed connections<\/td>Sharp increases indicate instabilities.<\/td><\/tr>
              Connections Timed Out<\/strong><\/td>Connections dropped unexpectedly<\/td>Indicates networking or idle-time issues.<\/td><\/tr>
              Connection Duration<\/strong><\/td>Avg time connections remain open<\/td>Useful for capacity planning.<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
              \n\n\n\n
              5\ufe0f\u20e3 System.Net.Http \u2014 Outbound HTTP Client Metrics<\/strong><\/h1>\n\n\n\n
              Metric<\/th>Meaning<\/th>Why It Matters<\/th><\/tr><\/thead>
              Requests Started\/sec<\/strong><\/td>Outbound calls initiated<\/td>Helps measure dependency load.<\/td><\/tr>
              Requests Failed\/sec<\/strong><\/td>Outbound failures<\/td>Useful for detecting flaky downstream services.<\/td><\/tr>
              Current HTTP\/1.1 Connections<\/strong><\/td>Active pooled connections<\/td>Helps identify connection pool exhaustion.<\/td><\/tr>
              HTTP\/2 Streams<\/strong><\/td>Streams in use<\/td>Critical for gRPC or HTTP\/2 workloads.<\/td><\/tr>
              DNS Lookup Duration<\/strong><\/td>Time taken for DNS resolution<\/td>Slow DNS = global latency issues.<\/td><\/tr>
              Sockets Queued<\/strong><\/td>Pending socket requests<\/td>Too many \u21d2 networking bottleneck.<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
              \n\n\n\n
              6\ufe0f\u20e3 Microsoft.EntityFrameworkCore \u2014 Database & Query Performance<\/strong><\/h1>\n\n\n\n
              Metric<\/th>Meaning<\/th>Why It\u2019s Critical<\/th><\/tr><\/thead>
              Queries Executed\/sec<\/strong><\/td>Database query rate<\/td>Detects DB overload & slow query patterns.<\/td><\/tr>
              Active DbContexts<\/strong><\/td>Number of active EF contexts<\/td>High values = context leaks or too many parallel queries.<\/td><\/tr>
              Command Execution Count<\/strong><\/td>DB commands executed<\/td>Measures DB workload intensity.<\/td><\/tr>
              Optimistic Concurrency Failures<\/strong><\/td>Version conflicts<\/td>Indicates concurrency problems & row contention.<\/td><\/tr>
              Queries Compilation Events<\/strong><\/td>EF query compilation<\/td>High compilation rate = missing compiled query reuse \u2192 performance loss.<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
              \n\n\n\n
              7\ufe0f\u20e3 Additional Important Diagnostic Signals<\/strong><\/h1>\n\n\n\n
              Metric<\/th>Meaning<\/th>Why It’s Useful<\/th><\/tr><\/thead>
              GC Fragmentation %<\/strong><\/td>How fragmented the heap is<\/td>Fragmentation increases GC time & reduces memory efficiency.<\/td><\/tr>
              GC Budget<\/strong><\/td>Target allocation for next GC<\/td>Helps understand upcoming GC cycles.<\/td><\/tr>
              JIT Time (ms\/sec)<\/strong><\/td>Time spent JIT-compiling code<\/td>Affects startup and \u201cwarm-up\u201d performance.<\/td><\/tr>
              Assemblies Loaded<\/strong><\/td>Number of loaded assemblies<\/td>Too many \u2192 high memory + startup time.<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
              \n\n\n\n
              \ud83c\udfaf Summary: Why These Metrics Matter<\/strong><\/h1>\n\n\n\n
              This table covers all critical metrics<\/strong> for diagnosing:<\/p>\n\n\n\n
                \n
              • High CPU<\/li>\n\n\n\n
              • Memory leaks<\/li>\n\n\n\n
              • High GC pressure<\/li>\n\n\n\n
              • Large object allocations<\/li>\n\n\n\n
              • ThreadPool starvation<\/li>\n\n\n\n
              • Lock contention<\/li>\n\n\n\n
              • Slow database queries<\/li>\n\n\n\n
              • HTTP failures & timeouts<\/li>\n\n\n\n
              • Real-time connection pressure<\/li>\n\n\n\n
              • Throughput & latency degradation<\/li>\n\n\n\n
              • Container OOM kills<\/li>\n\n\n\n
              • Cold-start & JIT issues<\/li>\n<\/ul>\n\n\n\n
                dotnet-counters<\/strong> is the first tool<\/em> you should use during:<\/p>\n\n\n\n
                  \n
                • Load Testing<\/li>\n\n\n\n
                • Performance Engineering<\/li>\n\n\n\n
                • CPU\/Memory profiling<\/li>\n\n\n\n
                • Cloud production incidents<\/li>\n\n\n\n
                • GC or memory leak investigations<\/li>\n<\/ul>\n\n\n\n
                  \n\n\n\n
                  <\/p>\n","protected":false},"excerpt":{"rendered":"
                  \u2705 dotnet-counters \u2013 Command Reference (Explained Simply) When you run: You see 4 main commands: Below is a simple explanation for each. \ud83d\udfe6 1. dotnet-counters monitor Real-time monitoring (LIVE metrics)… <\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_joinchat":[],"footnotes":""},"categories":[11138],"tags":[],"class_list":["post-54158","post","type-post","status-publish","format-standard","hentry","category-best-tools"],"_links":{"self":[{"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/posts\/54158","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/comments?post=54158"}],"version-history":[{"count":1,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/posts\/54158\/revisions"}],"predecessor-version":[{"id":54164,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/posts\/54158\/revisions\/54164"}],"wp:attachment":[{"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/media?parent=54158"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/categories?post=54158"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/tags?post=54158"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}