Home/ Questions/Q 7019091
In Process

The Archive Base Latest Questions

Editorial Team
  • 0
Asked: 2026-05-27T23:08:18+00:00

When reading from InputStreams, how do you decide what size to use for the

  • 0

When reading from InputStreams, how do you decide what size to use for the byte[]? 

int nRead;
byte[] data = new byte[16384]; // <-- this number is the one I'm wondering about

while ((nRead = is.read(data, 0, data.length)) != -1) {
  ...do something..
}

When do you use a small one vs a large one? What are the differences? Does the number want to be in increments of 1024? Does it make a difference if it is an InputStream from the network vs the disk?

Thanks much, I can’t seem to find a clear answer elsewhere.

Share

Leave an answer

You must login to add an answer.

Need An Account,

1 Answer

  1. Editorial Team

    Most people use powers of 2 for the size.
    If the buffer is at least 512 bytes, it doesn’t make much difference ( < 20% )

    For network the optimal size can be 2 KB to 8 KB (The underlying packet size is typically up to ~1.5 KB) For disk access, the fastest size can be 8K to 64 KB. If you use 8K or 16K you won’t have a problem.

    Note for network downloads, you are likely to find you usually don’t use the whole buffer. Wasting a few KB doesn’t matter much for 99% of use cases.

    • 0