Re: files/process scaling problem? (was: [PATCH] Export shmem_file_setup and shmem_getpage for DRM-GEM)

[Keith Packard <keithp@keithp.com>]

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On Mon, 2008-08-04 at 01:35 +0200, Ingo Oeser wrote:

> What actions on many thousand fds are supported poorly or not at all?
> Are you only concerned about the memory requirements?

I didn't notice that the change in the maximum number of fds per process
from 1024 to 1024*1024 back in February. That makes it possible,
although requiring root privs, to allocate enough fds for this to work.

The other issue is that several important applications (including the X
server) use select instead of poll, and they have a small maximum number
of fds that they support. It seems like this could be worked around by
dup2'ing the shmem fds up a ways.

> Please elaborate or point me to a place where you did already :-)

I should have looked at fs/file.c.

-- 
keith.packard@intel.com

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