Re: FD Limits

Mark Hemment (
Tue, 19 Nov 1996 20:40:59 +0000 (GMT)

On Mon, 18 Nov 1996, Jared Mauch wrote:
> Here is a patch of mine to do just what you want. I think it
> is very important to put this patch into the kernel as most modern OS'es
> (Solaris, OSF/1, etc..) have higher limits of at least 1024 per process.
> -#define NR_OPEN 256
> +#define NR_OPEN 1024

Agreed, Linux does need higher limits for servers.
Unfortunately, increasing NR_OPEN pushes up the memory overhead per task
(via struct files_struct) - using over 4K (quite a bit over 4K given how
kmalloc() works) - is a bit on the high side for most processes.

For truly dynamic limits, the structure and use of files_struct needs to be
changed. Hmmm, might give this a go...