最快的C ++地图，用于在实时应用程序中执行最坏情况的时间？

Question

I'm trying to figure out how I want to store timed events in a real time audio app that may hop around in time a lot, and needs to run with the lowest latency possible. Basically the engine knows what time 'now' is, but 'now' may be non-linear, and there be multiple 'nows' in the future. I'm wondering if:

a) a C++ map of some time keyed by time values is even feasible, when there could be thousands of entries b) which map or hash table implementation will give me the best performance where best means lowest worst case execution, not lowest average. An implementation that even once in a while takes a really long time will be unusable, something with a more deterministic result would be better. c) for a bunch of events sharing the same now, should one use some sort of hash multi map or link a list of all events at a given time?

I'm open to any other suggestions of how to do this too, or pointers to resources. Time is encoded in it's own format, representing sections:bars:beats:ticks

thanks! iain

Answer 1

Nothing can save you from having to profile your code and see for yourself.

Make the data type as easy to change as possible, keep everything modular and parameterised, and then just run some tests.

Start with std::multimap and std::unordered_multimap , with time as the key. Both should have pretty good performance. Try a few different allocators, too.