Through a single management interface (/proc/rxctl), the module is configured to dynamically add / remove RAM disks and support future features, on-the-fly. Such an open source implementation does not exist under Linux! For the most part, general functionality is handled via the rxadm user land tool. See RapidCache for details on rxcache mapping / unmapping and more.
Manual Page
The manual page to the rxadm user land tool (man 1 rxadm):
RXADM(1) GENERAL COMMANDS RXADM(1)
NAME
rxadm - An administration tool to manage the RapidDisk (rxdsk) RAM disk
devices and RapidCache (rxcache) mappings.
SYNOPSIS
rxadm [ -h | -v ] function [parameters: unit | size | src & dest |
cache & source & block size ]
DESCRIPTION
rxadm is a RapidDisk (rxdsk) module management tool. The tool allows
the user to list all attached rxdsk devices, with the ability to dynam‐
ically attach a new rxdsk block devices and detach existing ones. It
also is capable of mapping and unmapping a rxd volume to any block
device via the RapidCache (rxcache) kernel module.
Options
-h Invoke the help menu.
-v Display the version number.
Function
--attach
Dynamically attach new rxdsk devices.
--detach
Dynamically detach rxdsk devices.
--list List all attached rxdsk devices.
--short-list
List all attached rxdsk devices in script friendly format.
--flush
Erase all data to a specified rxdsk device (dangerous).
--resize
Dynamically grow the size of an existing rxdsk device.
--archive
Using zlib, archive an rxdsk device to a data file.
--restore
Using zlib, restore an rxdsk device from an archived data file.
--rxc-map
Map an rxdsk device as a caching node to anotther block device.
--rxc-unmap
Map an rxdsk device as a caching node to anotther block device.
Parameters (if applicable)
[size] Specify desired size of attaching RAM disk device in MBytes.
[unit] Specify unit number of RAM disk device to detach.
[src] Source path for archive/restore options.
[dest] Destination path for arcive/restore options.
[cache]
Specify rxd node to use as caching volume.
[source]
Specify block device to map cache to.
[block size]
Specify cache block size in KBytes (multiples of 4).
EXAMPLES
rxadm --list
rxadm --attach 64
rxadm --detach rxd2
rxadm --resize rxd2 128
rxadm --archive /dev/rxd0 rxd-052911.dat
rxadm --restore rxd-052911.dat /dev/rxd0
rxadm --rxc-map rxd1 /dev/sdb 8
rxadm --rxc-unmap rxc0
rxadm --flush rxd2
EXIT STATUS
rxadm returns a zero exit status if no error occurs during operation. A
non- zero value is returned on error.
AUTHORS
Original version: Petros Koutoupis (petros@petroskoutoupis.com)
SEE ALSO
View the rxdsk project page: http://rxdsk.petroskoutoupis.com
Linux Oct 16 2010 RXADM(1)
Command Line Examples
To list all attached rxdsk volumes:
$ sudo rxadm --list rxadm 1.3.1 Copyright 2011 Petros Koutoupis List of rxdsk device(s): Device 1: rxd0 Size: 67108864 Device 2: rxd1 Size: 33554432
To attach a new rxdsk volume (128 MB in example):
$ sudo rxadm --attach 128 rxadm 1.3.1 Copyright 2011 Petros Koutoupis Attached device rxd0 of size 128 Mbytes
Note that all newly attached volumes will appear in the /dev directory path (e.g. /dev/rxd0).
To detach an existing rxdsk volume:
$ sudo rxadm --detach rxd2 rxadm 1.3.1 Copyright 2011 Petros Koutoupis Detached device rxd2
To resize an existing rxdsk volume:
$ sudo rxadm --resize rxd0 128 rxadm 1.3.1 Copyright 2011 Petros Koutoupis Resized device rxd0 to 128 Mbytes
To archive an existing rxdsk volume:
$ sudo rxadm --archive rxd0 rxd0-bak.dat rxadm 2.0b Copyright 2011-2012 Petros Koutoupis Initiating the archival process. Currently deflating... Done.
Note - It is advised to unmount the rxdsk volume before archiving.
To restore an archived volume to an existing rxdsk volume:
$ sudo rxadm --restore rxd0-bak.dat rxd1 rxadm 2.0b Copyright 2011-2012 Petros Koutoupis Initiating the restoration process. Currently inflating... Done.
To view the module's current settings:
$ cat /proc/rxctl RapidDisk (rxdsk) 1.3 Maximum Number of Attachable Devices: 128 Number of Attached Devices: 0
See RapidCache for details on rxcache mapping / unmapping and more.
The pyRxAdm Graphical Wrapper
The pyRxAdm graphical wrapper is a Python / pyGTK written utility that relies heavily upon the rxadm command line management utility to manage rxdsk/rxcache volumes/mappings. Using it you can list, attach & detach volumes, map & unmap cache mappings, and archive & restore volumes. After installation (and ensuring that rxadm is in your current working path), type the following at the command line to bring up the graphical application (you can easily create a shortcut to this, note the icon and python file can be found in /opt/rxadm):
$ sudo python /opt/rxadm/pyRxAdm.py
In a future release, the third column may become more descriptive but at the moment, it will only list the size of an rxdsk volume in bytes and the volumes in an rxcache mapping. Some other notes on the graphical wrapper include: (1) You cannot specify rxcache mapping chunk sizes. (2) You cannot view rxcache detailed statistics. (3) You cannot do a dynamic rxdsk resizing. All of this stuff are more appropriate to handle from the command line interface by an advanced user.