EtherDream/QuickReader

With a stream reader, you can read the data in the specified format while downloading, which makes the user experience better. You don't have to do the chunk slicing and buffering yourself, the reader does all that.

Without it, you would have to wait for all the data to be downloaded before you could read it (e.g., via DataView). Since JS doesn't support structures, you have to pass in an offset parameter for each read, which is inconvenient to use.

The above two cases do the same thing, but the await one is 50x to 200x slower than the no-await. On Chrome it's even ~2000x slower if the console is open (only ~500 await/ms).

This test seems meaningless, but in fact, sometimes we call await heavily in an almost synchronous logic, such as an async query function that will mostly hit the memory cache and return.

Reading data from a stream has the same issue. For a single integer or tiny text, it takes only a few bytes, in most cases, it can be read directly from the buffer without I/O calls, so await is unnecessary; await is only needed when the buffer is not enough.

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