I have a singleton NSOperationQueue that handles all of my network requests. I'm noticing, however, that when I have one particularly long operation running (this particular operation takes at least 25 seconds), my other operations don't run until it completes.

maxConcurrentOperationCount is set to NSOperationQueueDefaultMaxConcurrentOperationCount, so I don't believe that's the issue.

Any reason why this would be happening? Besides spawning multiple NSOperationQueues (a solution that I'm not sure would work, nor am I sure it's a good idea), what's the best way to fix this problem?

Thanks.