On 2004-11-02, Peter Simons
John Goerzen writes:
Read and process the file in blocks:
I don't think that would really save much memory [...]
Given that the block-oriented approach has constant space requirements, I am fairly confident it would save memory.
Perhaps a bit, but not a significant amount.
and in fact, would likely just make the code a lot more complex. It seems like a simple wrapper around hGetContents over a file that uses block buffering would suffice.
Either your algorithm can process the input in blocks or it cannot. If it can, it doesn't make one bit a difference if you do I/O in blocks, because your algorithm processes blocks anyway. If your algorithm is *not* capable of
Yes it does. If you don't set block buffering, GHC will call read() separately for *every* single character. (I've straced stuff!) This is a huge performance penalty for large files. It's a lot more efficient if you set block buffering in your input, even if you are using interact and lines or words to process it. -- John