診斷用戶端程式庫

發行項
02/25/2024

本文適用於：✔️適用於目標應用程式的 .NET Core 3.0 SDK 和更新版本，要使用程式庫的 .NET Standard 2.0。

Microsoft.Diagnostics.NETCore.Client (也稱為診斷用戶端程式庫) 是受控程式庫，可讓您與 .NET Core 執行階段 (CoreCLR) 互動，以進行各種診斷相關工作，例如透過 EventPipe 進行追蹤、要求傾印或附加 ICorProfiler。此程式庫是許多診斷工具背後的備份程式庫，例如 dotnet-counters、dotnet-trace、dotnet-gcdump、dotnet-dump和 dotnet-monitor 等工具。您可以使用此程式庫為特定案例撰寫自訂的診斷工具。

您可以將 PackageReference 新增至專案，以取得 Microsoft.Diagnostics.NETCore.Client。套件會裝載在 NuGet.org 上。

下列各節中的範例會示範如何使用 Microsoft.Diagnostics.NETCore.Client 程式庫。其中一些範例也會示範如何使用 TraceEvent 程式庫剖析事件承載。

附加至程序並列印所有 GC 事件

此程式碼片段會示範如何使用 .NET 執行階段提供者搭配資訊層級上的 GC 關鍵字，來啟動 EventPipe 工作階段。其中也會示範如何使用 TraceEvent 程式庫提供的 EventPipeEventSource 類別來剖析傳入事件，並即時將其名稱列印到主控台。

using Microsoft.Diagnostics.NETCore.Client;
using Microsoft.Diagnostics.Tracing;
using Microsoft.Diagnostics.Tracing.EventPipe;
using Microsoft.Diagnostics.Tracing.Parsers;
using System;
using System.Collections.Generic;
using System.Diagnostics.Tracing;

public class RuntimeGCEventsPrinter
{
    public static void PrintRuntimeGCEvents(int processId)
    {
        var providers = new List<EventPipeProvider>()
        {
            new EventPipeProvider("Microsoft-Windows-DotNETRuntime",
                EventLevel.Informational, (long)ClrTraceEventParser.Keywords.GC)
        };

        var client = new DiagnosticsClient(processId);
        using (EventPipeSession session = client.StartEventPipeSession(providers, false))
        {
            var source = new EventPipeEventSource(session.EventStream);

            source.Clr.All += (TraceEvent obj) => Console.WriteLine(obj.ToString());

            try
            {
                source.Process();
            }
            catch (Exception e)
            {
                Console.WriteLine("Error encountered while processing events");
                Console.WriteLine(e.ToString());
            }
        }
    }
}

撰寫核心傾印

此範例會示範如何使用 DiagnosticsClient 來觸發核心傾印的集合。

using Microsoft.Diagnostics.NETCore.Client;

public partial class Dumper
{
    public static void TriggerCoreDump(int processId)
    {
        var client = new DiagnosticsClient(processId);
        client.WriteDump(DumpType.Normal, "/tmp/minidump.dmp");
    }
}

當 CPU 使用量超過閾值時觸發核心傾印

此範例會示範如何監視 .NET 執行階段所發佈的 cpu-usage 計數器，並在 CPU 使用量超過特定傾印時要求傾印。

using Microsoft.Diagnostics.NETCore.Client;
using Microsoft.Diagnostics.Tracing;
using Microsoft.Diagnostics.Tracing.EventPipe;
using Microsoft.Diagnostics.Tracing.Parsers;
using System;
using System.Collections.Generic;
using System.Diagnostics.Tracing;

public partial class Dumper
{
    public static void TriggerDumpOnCpuUsage(int processId, int threshold)
    {
        var providers = new List<EventPipeProvider>()
        {
            new EventPipeProvider(
                "System.Runtime",
                EventLevel.Informational,
                (long)ClrTraceEventParser.Keywords.None,
                new Dictionary<string, string>
                {
                    ["EventCounterIntervalSec"] = "1"
                }
            )
        };
        var client = new DiagnosticsClient(processId);
        using (var session = client.StartEventPipeSession(providers))
        {
            var source = new EventPipeEventSource(session.EventStream);
            source.Dynamic.All += (TraceEvent obj) =>
            {
                if (obj.EventName.Equals("EventCounters"))
                {
                    var payloadVal = (IDictionary<string, object>)(obj.PayloadValue(0));
                    var payloadFields = (IDictionary<string, object>)(payloadVal["Payload"]);
                    if (payloadFields["Name"].ToString().Equals("cpu-usage"))
                    {
                        double cpuUsage = Double.Parse(payloadFields["Mean"].ToString());
                        if (cpuUsage > (double)threshold)
                        {
                            client.WriteDump(DumpType.Normal, "/tmp/minidump.dmp");
                        }
                    }
                }
            };
            try
            {
                source.Process();
            }
            catch (Exception) {}
        }
    }
}

觸發指定秒數的 CPU 追蹤

此範例會示範如何使用預設 CLR 追蹤關鍵字和範例分析工具，觸發一段時間內的 EventPipe 工作階段。然後讀取輸出資料流，並將位元組寫入檔案。基本上，這是 dotnet-trace 在內部用來寫入追蹤檔案的內容。

using Microsoft.Diagnostics.Tracing;
using Microsoft.Diagnostics.Tracing.Parsers;
using Microsoft.Diagnostics.NETCore.Client;
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Diagnostics.Tracing;
using System.IO;
using System.Threading.Tasks;

public partial class Tracer
{
    public void TraceProcessForDuration(int processId, int duration, string traceName)
    {
        var cpuProviders = new List<EventPipeProvider>()
        {
            new EventPipeProvider("Microsoft-Windows-DotNETRuntime", EventLevel.Informational, (long)ClrTraceEventParser.Keywords.Default),
            new EventPipeProvider("Microsoft-DotNETCore-SampleProfiler", EventLevel.Informational, (long)ClrTraceEventParser.Keywords.None)
        };
        var client = new DiagnosticsClient(processId);
        using (var traceSession = client.StartEventPipeSession(cpuProviders))
        {
            Task copyTask = Task.Run(async () =>
            {
                using (FileStream fs = new FileStream(traceName, FileMode.Create, FileAccess.Write))
                {
                    await traceSession.EventStream.CopyToAsync(fs);
                }
            });

            Task.WhenAny(copyTask, Task.Delay(TimeSpan.FromMilliseconds(duration * 1000)));
            traceSession.Stop();
        }
    }
}

列印發佈診斷通道的程序名稱

此範例會示範如何使用 DiagnosticsClient.GetPublishedProcesses API 來列印發佈診斷 IPC 通道的 .NET 程序名稱。

using Microsoft.Diagnostics.NETCore.Client;
using System;
using System.Diagnostics;
using System.Linq;

public class ProcessTracker
{
    public static void PrintProcessStatus()
    {
        var processes = DiagnosticsClient.GetPublishedProcesses()
            .Select(Process.GetProcessById)
            .Where(process => process != null);

        foreach (var process in processes)
        {
            Console.WriteLine($"{process.ProcessName}");
        }
    }
}

即時剖析事件

此範例會提供我們建立兩個工作的範例，其中一個會剖析透過 EventPipeEventSource 即時傳入的事件，另一個會讀取使用者輸入的主控台輸入，以發出讓程式結束的訊號。如果目標應用程式在使用者按下 Enter 之前結束，應用程式會正常結束。否則，inputTask 會將 Stop 命令傳送至管道並正常結束。

using Microsoft.Diagnostics.NETCore.Client;
using Microsoft.Diagnostics.Tracing;
using Microsoft.Diagnostics.Tracing.EventPipe;
using Microsoft.Diagnostics.Tracing.Parsers;
using System;
using System.Collections.Generic;
using System.Diagnostics.Tracing;
using System.Threading.Tasks;

public partial class Tracer
{
    public static void PrintEventsLive(int processId)
    {
        var providers = new List<EventPipeProvider>()
        {
            new EventPipeProvider("Microsoft-Windows-DotNETRuntime",
                EventLevel.Informational, (long)ClrTraceEventParser.Keywords.Default)
        };
        var client = new DiagnosticsClient(processId);
        using (var session = client.StartEventPipeSession(providers, false))
        {

            Task streamTask = Task.Run(() =>
            {
                var source = new EventPipeEventSource(session.EventStream);
                source.Clr.All += (TraceEvent obj) => Console.WriteLine(obj.EventName);
                try
                {
                    source.Process();
                }
                // NOTE: This exception does not currently exist. It is something that needs to be added to TraceEvent.
                catch (Exception e)
                {
                    Console.WriteLine("Error encountered while processing events");
                    Console.WriteLine(e.ToString());
                }
            });

            Task inputTask = Task.Run(() =>
            {
                Console.WriteLine("Press Enter to exit");
                while (Console.ReadKey().Key != ConsoleKey.Enter)
                {
                    Task.Delay(TimeSpan.FromMilliseconds(100));
                }
                session.Stop();
            });

            Task.WaitAny(streamTask, inputTask);
        }
    }
}

附加 ICorProfiler 分析工具

此範例會示範如何透過分析工具附加將 ICorProfiler 附加至程序。

using System;
using Microsoft.Diagnostics.NETCore.Client;

public class Profiler
{
    public static void AttachProfiler(int processId, Guid profilerGuid, string profilerPath)
    {
        var client = new DiagnosticsClient(processId);
        client.AttachProfiler(TimeSpan.FromSeconds(10), profilerGuid, profilerPath);
    }
}