I've read somewhere that DOS/Windows reads an entire cluster at a time. This size can vary anywhere between 4KB and 32KB. But this is hard-coded into the OS. So, there's not much you can do. If you're using an NTFS file system with 4KB clusters, then that means each read operation that is 4KB or less will grab 4KB. Even if you're just reading one byte from a file. If you want to read 5000 bytes, it will read 8 kilobytes. There's no way around it. In Perl, you can turn off buffering, and maybe that will help, but I'm no expert.

The sysread() function will give you however many bytes you want to get, but that doesn't mean that at the lowest level you're forcing the OS to read smaller chunks. You can't.

In reply to Re: Perl reads minimum 8KB from files. Can this be lowered? by harangzsolt33
in thread Perl reads minimum 8KB from files. Can this be lowered? by sectokia

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