Re: [RFC PATCH] getvalues(2) prototype

Greg KH
2022-03-23T07:16:49Z

On Tue, Mar 22, 2022 at 08:27:12PM +0100, Miklos Szeredi wrote:
> Add a new userspace API that allows getting multiple short values in a
> single syscall.
>
> This would be useful for the following reasons:
>
> - Calling open/read/close for many small files is inefficient. E.g. on my
> desktop invoking lsof(1) results in ~60k open + read + close calls under
> /proc and 90% of those are 128 bytes or less.

As I found out in testing readfile():
https://lore.kernel.org/r/20200704140250.423345-1-gregkh@linuxfoundation.org

microbenchmarks do show a tiny improvement in doing something like this,
but that's not a real-world application.

Do you have anything real that can use this that shows a speedup?

thanks,

greg k-h