Blog
Mert Özen's blog posts on software development, backend, frontend, and DevOps.
C# Synchronization: lock, Interlocked, SemaphoreSlim and Concurrent Collections
Why sold++ never reaches a million: race conditions and the check-then-act race. The rules of lock and why you can't await inside it, atomic counters and CompareExchange with Interlocked, the SemaphoreSlim pattern for an async cache, ConcurrentDictionary factories that run more than once and the Lazy<T> fix.
Producer/Consumer with C# Channels: Backpressure, Bounded Channels and Pipelines
An async queue with System.Threading.Channels: why three orders fit into a channel with a capacity of two, Writer/Reader and Complete, the WaitToReadAsync/TryRead loop, FullMode options and itemDropped on bounded channels, multiple consumers, an order pipeline that passes failures on with Complete(ex), and the cost of forgetting Complete.
C# Timers and Waiting: PeriodicTimer, WaitAsync and Task.Delay
Overlapping callbacks in System.Threading.Timer, overlap-free periodic work with .NET 6 PeriodicTimer, how Thread.Sleep and Task.Delay affect the thread pool and how precise Task.Delay is, System.Timers.Timer swallowing exceptions, WaitAsync not canceling the operation, retries with backoff and jitter, and a timer collected by the GC.
C# Async and .NET 8: TimeProvider, ConfigureAwaitOptions, Parallel.ForAsync and CancelAsync
On .NET 6 we wrote our own IClock; on .NET 8, TimeProvider and FakeTimeProvider make a 15-minute wait take 0 ms in a test. SuppressThrowing, which waits without throwing, and its Task<T> trap, ForceYielding, Parallel.ForAsync, which takes an index range directly, and CancelAsync, which runs callbacks without blocking the caller.
C# Async and .NET 9–10: Task.WhenEach, the Lock Type and Async LINQ in the Framework
The .NET 9 Task.WhenEach that replaces the WhenAny loop and how it handles failed tasks, System.Threading.Lock recognized by the C# 13 lock statement and its limits (CS9216, CS1996, CS4007, CS9202), async LINQ moving into the framework in .NET 10, async Select, and fixing the clash with the System.Linq.Async package.