Re: [PATCH 0/3] readfile(2): a new syscall to make open/read/close faster

Matthew Wilcox
2020-07-05T02:16:43Z

On Sun, Jul 05, 2020 at 04:06:22AM +0200, Jan Ziak wrote:
> Hello
>
> At first, I thought that the proposed system call is capable of
> reading *multiple* small files using a single system call - which
> would help increase HDD/SSD queue utilization and increase IOPS (I/O
> operations per second) - but that isn't the case and the proposed
> system call can read just a single file.
>
> Without the ability to read multiple small files using a single system
> call, it is impossible to increase IOPS (unless an application is
> using multiple reader threads or somehow instructs the kernel to
> prefetch multiple files into memory).

What API would you use for this?

ssize_t readfiles(int dfd, char **files, void **bufs, size_t *lens);

I pretty much hate this interface, so I hope you have something better
in mind.