Using the ioDrive as Swap Space under Linux

For instructions on using an ioDrive as swap space under a different operating system, consult the user guide for that operating system.

Follow the instructions based on the version of your driver.

Instructions for Driver Versions 2.1.x
Instructions for Driver Versions 1.2.x
Using Multiple Devices under Linux

Instructions for Driver Versions 2.1.x

To safely use the ioDrive as swap space requires passing the preallocate_memory kernel module parameter. The recommended method for providing this parameter is to add the following line to the /etc/modprobe.d/iomemory-vsl.conf file:

options iomemory-vsl preallocate_memory=1072

Where 1072 is the serial number for the device obtained from fio-status. For multiple devices separate serial numbers with a comma. However, using multiple swap targets under linux results in reduced performance, and is not recommended.

Notes:

• Be sure to provide the serial numbers for the ioMemory Modules, not the adapter.
• A 4 KB sector size format is required for swap—this reduces the driver memory footprint to reasonable levels.
• The preallocate_memory module parameter is necessary to have the drive usable as swap space. This will ensure the drive is crash-free during operation. See the appendix Using Module Parameters in the ioDrive Linux User Guide for more information on setting this parameter.
• You must have 400 MB of free RAM per 80GB of ioDrive capacity (formatted to 4 KB block size) to enable the ioDrive with pre-allocation enabled for use as swap. Attaching an ioDrive, with pre-allocation enabled, without sufficient RAM may result in the loss of user processes and system instability.
• The preallocate_memory parameter is recognized by the ioMemory VSL at load time, but the requested memory is not actually allocated until the specified device is attached.

1. Enable swap support in /etc/modprobe.d/iomemory-vsl.conf by adding the options line. Replace <your_iodrive_serial_number_here> with the actual serial number of the ioDrive to be used as swap space.

options iomemory-vsl preallocate_memory=<your_iodrive_serial_number_here>

2. Restart the computer or unload and reload the ioDrive driver to enable the preallocate_memory driver option.

3. Add an entry for the ioDrive (/dev/fioa) in /etc/fstab, assuming /dev/fioa is to be used as swap space.

/dev/fioa none swap sw 0 0

4. Initialize the ioDrive as swap space.

$ mkswap /dev/fioa

5. To disable/reenable the swap space, run these commands:

$ swapoff -a

$ swapon -a


swapon -s, cat /proc/swaps, cat /proc/meminfo, or top can be used to monitor swap usage.

Instructions for Driver Versions 1.2.x

Swap support is deprecated for 1.2.x drivers. For best performance, we recommend upgrading the driver to 2.1.x.

Using Multiple Devices under Linux

Using multiple swap targets under linux results in reduced performance, and is not recommended.