Thu May 23 12:13:58 1996
Yasushi Saito
Overview
Unix Fast File System(UFS from now on) is a
readonly
file system that
can read common ufs file system on a local disk.
Design and Implementation
It's an another kind of file system extension.
It's a full fledged file system except that you can't write on it.
It has extensive block cache and inode cache. The performance is
comparable to the DEC OSF/1 UFS file system. (about 15% slower with
warm cache, almost same performance with cold cache).
Note : I'm kind of cheating on caches. It's 2-way set associative with LRU
purging on each line. We should implement full associative one.
Using the service
UFS is usually loaded via nanny, so
no special command is required to load it.
When UFS is loaded, it installs inself in the
name server.
To use the file system, you first have to mount it like below.
!>mount rz3a ufs /usr
The first argument to mount specifies the local device name.
You can see the list of device names by
!>show devices
Caveats
yasushi@cs.washington.edu