Undo Enumerable.AsParallel(), going back to serial mode

Question

Assume you have a LINQ query like

source.AsParallel().Where(expensiveOperation).Select(cheapOperation)

I suppose in this case Select also runs in parallel execution mode. Maybe it's just a cheap operation like i => i*2, so is there a way to stop parallel execution at a point of querying with chained methods?

(maybe like .AsParallel().Where(expensiveOp).AsSerial?().Select(cheapOp)?)

Absorptance

I belive PLINQ is smart and executes the Where() together with the Select(). So, even when Select() is cheap, you probably don't need to force it to be sequential. But you'll have to measure that for yourself. – Cissoid

Answer 1

The operation you're looking for is AsSequential.

source.AsParallel().Where(expensiveOp).AsSequential().Select(cheapOp)

Madlynmadman

looks like I was wrong on vocabulary haha. Thanks for noting. I literally looked for AsSerial() in docs for a few mins. – Absorptance