Performance Hotpath Risk

Why this rule exists

Thread.Sleep blocks a thread-pool thread. LINQ inside a loop turns O(n) into O(n^2). Unbounded list growth turns a 100-item test into an OOM at 100k items. None of these show up in unit tests.

Code example

+ foreach (var id in ids)
+ {
+     var match = users.FirstOrDefault(u => u.Id == id);
+     Thread.Sleep(10);
+ }

+ var byId = users.ToDictionary(u => u.Id);
+ foreach (var id in ids)
+ {
+     var match = byId.GetValueOrDefault(id);
+     await Task.Delay(10, ct);
+ }

Configuration

Disable or adjust the severity of this rule in .gauntletci.json:

{
  "rules": {
    "GCI0044": { "enabled": true, "severity": "Info" }
  }
}

See Configuration for the full schema.

Related rules

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