which data structure is good for temporary big binary data storage?

Question

Plan to have a data structure to store temporary binary data in the memory for analysis.

The max size of the data will be about 10MB .

data will be added at the end 408 bytes at a time.

no search, retrieve operations on those temporary binary data.

data will be wipe out and the storage will be reused for next analysis.

questions:

1. which structure is good for this purpose? byte[10MB], List<bytes>(10MB), List<MyStruct>(24000), or ...?
2. how to quickly wipe out the data (not List.Clear(), just set the value to 0) for List or array?
3. If I say List.Clear(), the memory for this List will shrink or the capacity (memory) of the List is still there and no memory allocation when I call List.AddRange() after the Clear()?
4. List.Insert() will make the List larger or it just replace the existing item?

Answer 1

You will have to describe what you are doing more to give better answers but it sounds like you are worried about efficiency/perf so

1. byte[]
2. no need to clear the array, just keep track of where the 'end' of your current cycle is
3. n/a
4. n/a

Answer 2

using (System.IO.MemoryStream memStream = new System.IO.MemoryStream())
{
    Do stuff
} // the using ensures proper simple disposal occurs here so you don't have to worry about cleaning up.

Answer 3

If your data is usually the same size, and always under a certain size, use a byte array.

Create a byte[], and a int that lets you know where the end of the "full" part of that buffer stops and the "free" part starts. You never need to clear it; just overwrite what was there. The only problem with this is if your data is sometimes 100 kb, sometimes 10 MB, and sometimes a bit larger than you originally planned for.

List will be slower to use and larger in memory, although they handle various sizes of data out of the box.