CFS(4) CFS(4)
NAME
cfs - cache file system
SYNOPSIS
cfs -s [-rd] [-f partition]
cfs -a netaddr [-rd] [-f partition] [mtpt]
DESCRIPTION
Cfs is a user-level file server that caches information
about remote files onto a local disk. It is normally
started by the kernel at boot time, though users may start
it manually. Cfs is interposed between the kernel and a
network connection to a remote file server to improve the
efficiency of access across slow network connections such as
modem lines. On each open of a file cfs checks the consis-
tency of cached information and discards any old information
for that file.
Cfs mounts onto mtpt (default /) after connecting to the
file server.
The options are:
s the connection to the remote file server is on file
descriptors 0 and 1.
a netaddr
dial the destination netaddr to connect to a remote
file server.
r reformat the cache disk partition.
d turn on debugging
f partition
use file partition as the cache disk partition.
All 9P messages except read, clone, and walk (see intro(5))
are passed through cfs unchanged to the remote server. A
clone followed immediately by a walk is converted into a
clwalk. If possible, a read is satisfied by cached data.
Otherwise, the file server is queried for any missing data.
FILES
/dev/hd0cache
Default file used for storing cached data.
SOURCE
/sys/src/cmd/cfs
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