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Counters

Counters allow you to maintain shared numeric state across multiple clients.

They provide atomic updates, ensuring consistency even in distributed environments.

Why Use Counters?​

In distributed systems, multiple instances may update the same value.

Without coordination, this can lead to:

  • Lost updates
  • Incorrect counts
  • Race conditions

Counters ensure updates are applied safely.

Incrementing a Counter​

await client.Counters.AddAsync("counter:orders", 1);
  • Increments the counter by the given value
  • Safe across multiple clients

Getting the Value​

var result = await client.Counters.GetAsync("counter:orders");

if (result.Success)
{
    Console.WriteLine(result.Value);
}

Setting a Value​

await client.Counters.SetAsync("counter:orders", 100);
  • Sets the counter explicitly

Example: Tracking Active Workers​

await client.Counters.AddAsync("workers:active", 1);

// do work

await client.Counters.AddAsync("workers:active", -1);

This ensures accurate tracking even with multiple instances.

Key Properties​

  • Atomic updates
  • Consistent across nodes
  • No manual locking required

When to Use Counters​

Use counters when you need:

  • Tracking counts (users, jobs, requests)
  • Rate limiting
  • Shared numeric state

Important Notes​

  • Counters are safe for concurrent updates
  • Values are numeric
  • Works the same in InProc and Distributed modes

What’s Next​

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