Make Git slowdowns visible in daemon metrics (#2366)

* feat(server): expose daemon Git pressure metrics

Separate limiter queue wait from Git execution time and report subscription ownership so accumulating work is visible in the existing runtime log.

* fix(server): collect subscriptions in agent metrics

Reuse the existing agent snapshot during runtime flushes so WebSocket shutdown does not require an additional AgentManager method call.

* test(server): retry transient hub cleanup

packages/server/src/utils/run-git-command.ts

@@ -2,6 +2,10 @@ import { existsSync } from "node:fs";
 import pLimit from "p-limit";
 import type { Logger } from "pino";
 import type { ProcessEnvRecord } from "../server/paseo-env.js";
+import {
+  GitCommandRuntimeMetricsWindow,
+  type GitCommandRuntimeMetricsSnapshot,
+} from "./git-command-runtime-metrics.js";
 import { spawnProcess } from "./spawn.js";
 
 const DEFAULT_TIMEOUT_MS = 30_000;
@@ -10,6 +14,7 @@ const DEFAULT_STDERR_LIMIT = 2048;
 
 const gitConcurrency = parseInt(process.env.PASEO_GIT_CONCURRENCY ?? "8", 10) || 8;
 const gitLimit = pLimit(gitConcurrency);
+const gitRuntimeMetrics = new GitCommandRuntimeMetricsWindow(gitConcurrency);
 
 export interface GitCommandOptions {
   cwd: string;
@@ -81,6 +86,13 @@ export function stopGitCommandMetrics(): GitCommandMetricsSnapshot {
   };
 }
 
+export function snapshotGitCommandRuntimeMetrics(): GitCommandRuntimeMetricsSnapshot {
+  return gitRuntimeMetrics.snapshotAndReset({
+    active: gitLimit.activeCount,
+    pending: gitLimit.pendingCount,
+  });
+}
+
 function beginGitCommandMetric(): GitCommandMetricsState | null {
   const state = gitCommandMetricsState;
   if (!state) {
@@ -123,9 +135,11 @@ export function runGitCommand(
   args: string[],
   options: GitCommandOptions,
 ): Promise<GitCommandResult> {
-  return gitLimit(
+  const runtimeMetric = gitRuntimeMetrics.submit(getGitOperation(args));
+  const promise = gitLimit(
     () =>
       new Promise<GitCommandResult>((resolve, reject) => {
+        gitRuntimeMetrics.start(runtimeMetric);
         const timeout = options.timeout ?? DEFAULT_TIMEOUT_MS;
         const maxOutputBytes = options.maxOutputBytes ?? DEFAULT_MAX_OUTPUT_BYTES;
         const acceptExitCodes = options.acceptExitCodes ?? [0];
@@ -175,24 +189,28 @@ export function runGitCommand(
           callback();
         };
 
-        const finishMetricOnce = (metric: GitCommandMetric) => {
+        const finishMetricOnce = (metric: GitCommandMetric, timedOut = false) => {
           if (metricFinished) return;
           metricFinished = true;
           finishGitCommandMetric(metricsState, metric);
+          gitRuntimeMetrics.finish(runtimeMetric, { success: metric.success, timedOut });
         };
 
         const timer = setTimeout(() => {
           const error = new Error(`Git command timed out after ${timeout}ms: ${command}`);
           child.kill("SIGKILL");
-          finishMetricOnce({
-            args,
-            cwd: options.cwd,
-            startedAtMs: startedAt,
-            durationMs: Date.now() - startedAt,
-            exitCode: null,
-            signal: "SIGKILL",
-            success: false,
-          });
+          finishMetricOnce(
+            {
+              args,
+              cwd: options.cwd,
+              startedAtMs: startedAt,
+              durationMs: Date.now() - startedAt,
+              exitCode: null,
+              signal: "SIGKILL",
+              success: false,
+            },
+            true,
+          );
           settle(() => reject(error));
         }, timeout);
 
@@ -318,8 +336,14 @@ export function runGitCommand(
         });
       }),
   );
+  gitRuntimeMetrics.observeLimiter(gitLimit.activeCount, gitLimit.pendingCount);
+  return promise;
 }
 
 function formatGitCommand(args: string[]): string {
   return ["git", ...args].join(" ");
 }
+
+function getGitOperation(args: string[]): string {
+  return args[0] === "-c" ? (args[2] ?? "unknown") : (args[0] ?? "unknown");
+}