third-party/rrdtool-1.4.8/doc/rrdflushcached.html
rrdflushcached - Flush the values for a spcific RRD file from memory.
rrdtool flushcached [--daemon address] filename [filename ...]
The flushcached function connects to the rrdcached manpage, the RRD caching daemon, and issues a "flush" command for the given files. The daemon will put the files to the head of the update queue so they are written "soon". The status will be returned only after the files' pending updates have been written to disk.
filename
The name(s) of the RRD file(s) that are to be written to disk.
--daemon address
Address of the the rrdcached manpage daemon. If not specified, the RRDCACHED_ADDRESS environment variable must be set (see below). For a list of accepted formats, see the -l option in the the rrdcached manpage manual.
rrdtool flush --daemon unix:/var/run/rrdcached.sock /var/lib/rrd/foo.rrd
The following environment variables may be used to change the behavior of rrdtoolflushcached:
RRDCACHED_ADDRESS
If this environment variable is set it will have the same effect as specifying the --daemon option on the command line. If both are present, the command line argument takes precedence.
Florian Forster <octo at verplant.org>