> On Wed, Oct 11, 2000 at 11:36:43AM -0500, Morong, Gerry wrote:
> >
> > Red Hat 6.1 - 7.0 appear to have a 256 nfs/local mount limit. Is there a
> > tunable parameter to increase this? My Solaris 2.6 box will mount all 571
> > possible mounts we have here at the same time.
>
> No, there's no way to increase this limit. It is an artifact of how
> the VFS deals with non-device mounts like NFS and autofs. It allocates
> each of them a minor from the non-device (major 0), so there's a maximum
> of 256 nodev filesystem mounts. There's no easily implemented solution
> to this; the most likely solution will result from the increase in the
> size of dev_t in the 2.5 timeframe.
>
> There should be no limit to the total number of locally mounted
> filesystems.
>
> J
The switch to using 16bits for the minor number is the clean way to overcome
this limitation, but since that's quite a ways off, I wrote set of patches
to increase the limit in the 2.2 kernels.
The way it works is to change the non-device from a single major number (0) to
a list of major numbers used for that purpose. Once this limitation was removed,
I then ran into another limit. The RPC layer's method of searching for a port
to use, has a limit of about 800 ports that can be used. After changing that
algorithm, I got a set of patches that should allow over 7000 mounts (actually
more, if you're willing to use the major numbers of devices you don't have on
your system). I've used them to mount 2000 NFS filesystems at once on a few
of our systems.
I just have to figure out what legal process I have to go through to get
Intel to allow me to release them.
