cache filesystem for NFS

Bruce Perens (bruce@pixar.com)
Wed, 5 Jul 95 12:32 PDT


> From: Jim Nance <jlnance@isscad.com>
> This is in response to a message about caching NFS file to disk that was
> posted here a few days ago. [...] The basic idea was to cache NFS files to
> a local disk since NFS is slow. I have also seen a suggestion to do the same
> for CDROMS since they are also slow.

From: iialan@iifeak.swan.ac.uk (Alan Cox)
> This would be a big gain for paging. Having a non page flag so that binaries
> off CD-ROM page back/forth from swap would need more swap but avoid the
> penalties of slow CD-ROM seeks.

I think IRIX now implements "cachefs". This is a "cache filesystem" that is
a client of another mounted filesystem. The raw partition, server filesystem
mount point, and client filesystem mount point are passed to the mount() call.
The nice thing about it is that it doesn't have to know anything about the
server filesystem other than that it provides the standard filesystem
interface.

Besides cacheing NFS and CD-ROM, it's nice to cache magneto-optical disks.
NeXT saw a big performance increment when they did a disk-based cache for
their big slow magneto-optical.

Thanks

Bruce Perens

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