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File System Event callback only gets one event

Hello again,

This is more idle curiosity more than anything, but I find the FSEvents callback behavior odd.

I have created a File System Events stream and start it running. What I find odd, particularly in light of the API design which is clearly designed to handle large volumes of events, is that I never get any big batches of events passed to my callback routine, even when I start with a stream that asks for hundreds of thousands of historical events.

Every time my callback function is called, the numEvents parameter is 1. It processes one event and returns. When processing thousands of historical events, most of the CPU time is wasted in the run loop. According to Shark & sample, only 10% of the time is spent in my callback function. The other 90% is spent in the run loop. This makes me think that I could get up to an order of magnitude improvement in performance if the stream would just pass more than 1 event at a time to my callback.

I'm also surprised at the number of duplicate consecutive events. I could also deal with these more efficiently if I could process the events in larger batches.
--
James Bucanek

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