dd if=/dev/random of=/dev/null bs=always

Late last week I released 2.0.1b, with a bug fix (bug #5) in the rxadm admin tool and a few cleanup changes in some of the module print messages. More details can be read here: www.rapiddisk.org

I have also been working on an ARM based Linux distribution called RapidDisk LX which brings RapidDisk functionality as a SCSI Target. More details of it can be read here: lx.rapiddisk.org

This distribution has already been listed in the waiting list at DistroWatch.

To stay updated on this project, please follow the Google+ page.

Well, it has been quite some time since I posted an update here. A lot of new and exciting things have been happening with the RapidDisk project. For instance, there is now a new dedicated project website located at www.rapiddisk.org. This new website has been using the RapidDisk Google+ page as the venue for latest project updates.

Also, in recent weeks, I released a stable version of 1.4 alongside a patch to build for older 2.6.18 kernels; that is, for those still using Red Hat or CentOS 5.x.

I have been spending most of my free time focusing on the 2.0 beta release. I have made a lot of progress and continue to do so. I should have something available in the next two weeks. RapidDisk 2.0 introduces a new module alongside rxdsk.ko called RapidCache or rxcache.ko. The purpose of RapidCache is to use an rxdsk volume as a caching volume for any local/remote physical block device via the device-mapper framework. The only supported caching is Write-Through and Reads (safest for data integrity). I need to find some way to better gauge my performance benchmarks because in some cases, I see a 17% performance boost to the standalone SATA drive while in other cases I notice some slightly worse performance. Obviously, this is primarily intended for certain environments and I will provide all details on the Wiki as soon as I (1) test on other Linux kernels, (2) add support for it in the rxadm administration utility, (3) and capture some cleaner performance data points.

Once I release it into beta and make sure it is stable, I will then try to see about getting it into the Linux kernel’s staging tree.

I just released RapidDisk version 1.3.1b. The changelog documents the following changes:

• Added check in management utility to make sure that rxdsk node is present before archiving and restoring compressed/ decompressed images.

This is a very minor update and is mostly for the restoration portion of the utility so we just don’t accidentally create a file named /dev/rxd[x] instead of using an actual rxdsk volume, if that volume is not present on the system.

One other note, the same 1.3b patch to enable the module to build on kernel 2.6.18 will still work with this release.

For additional information on the RapidDisk project, please visit its official wiki page. Or to stay updated, just follow the project on the RapidDisk Google+ page.

As promised in the 1.3b release, I just uploaded a patch for RapidDisk 1.3 to be able to build and install the module on the older 2.6.18 Linux kernel. That is, if you are still using Red Hat or CentOS 5.x. To apply the patch, just navigate to the module/drivers/block path from the root of the project package, make sure the patch is copied in there, and type:

$ patch -p0< rxdsk1.3_linux-2.6.18.patch

For additional information on the RapidDisk project, please visit its official wiki page. Or to stay updated, just follow the project on the RapidDisk Google+ page.

I am writing to announce the release of my Linux RAM disk kernel module. Yes, the Linux kernel has the brd module already integrated into it, and also the zram module it the staging tree. And yes, you can instead utilize ramfs or tmpfs for RAM based file systems. But RapidDisk or rxdsk is a bit different.

Unlike brd or zram all attached RAM disk are populated on-the-fly with any user defined size and not during the module’s insertion (i.e. typically system bootup) with a fixed size. When you attach a new RAM disk, you can define sizes as little as 16 Mbytes and in theory as large as 1 TByte and possibly above and it is designed to allocate new kernel pages as needed; so it won’t steal all memory when the RAM disk is created.

Unlike ramfs or tmpfs, an rxdsk volume can easily be exported as a physical device across a SAN or simply allocated as a SWAP space which would become more ideal when the LZO compression is completed and stabilized.

This type of technology could be used for quick I/O storage (configured as a DRAM-based SSD with enabled syncing to persistent storage) and mounted as a block device labeled with a traditional file system and functioning as a traditional storage device; Application and/or database caching; File system meta-data caching; Virtualization (when data compression is developed and/or while running another data deduplication solution on top of the RAM disk); and as mention above, a CompCache replacement for enabling compressed swap space into RAM (again, when compression is developed).

For more details, please do not hesitate to visit the project’s wiki page. Here you will find details on how to check the source code out from the git repo, build & install it, among other things including performance numbers (writing 1 GByte sizes in 3 seconds!!!) to community involvement. The kernel module is licensed under the GPLv2 while the management utility is licensed under the GPLv3.

Note - So far this has only been tested and seen as fully functional on the 2.6.32 and 2.6.35 kernels.

Just a quick update. New patches have been uploaded to the project site of the SCSI Bus Analyzer Module (SCSITrace) on Sourceforge.net. These patches are for Red Hat Enterprise Linux 6 and cover the following kernels: 2.6.32-71.el6 and 2.6.32-71.18.1.el6 on x86 & AMD64/Intel64 architectures. You can download the files here.

The project is still in Beta status and more information can be found on our Wiki page dedicated to the project at http://wiki.petroskoutoupis.com/index.php5?title=SCSI_Trace.

I am just writing to announce the incremental release of my DrvAdm Linux 2.6 kernel (2.6.28 and above) storage administration utility. It is licensed under the GPL v3 and currently in version 10.09-3. This version addresses a corner case segmentation error which has only been seen on unsupported Linux platforms. Also addressed were typos found in the online help and manual page.

More can be read here: http://wiki.petroskoutoupis.com/index.php5?title=DrvAdm

I am just writing to announce the official release of my SCSI Bus Analyzer Module (scsitrace) 1.0 Beta for the Linux 2.6 kernels. A patch has been released for the Linux 2.6.35.4 kerne

I am just writing to announce the incremental release of my DrvAdm Linux 2.6 kernel specific storage administration utility. It is licensed under the GPL v3 and currently in version 10.09-2, the utility provides the capabilities to:

• add/remove/rescan for devices in the Linux 2.6 SCSI Subsystem
• reset the SCSI host, target, bus or all
• retrieve a list of all SCSI devices with detailed information
• receive a list of all SCSI hosts with detailed information
• view device partition tables, geometry / size
• dynamically modify parameters such as queue depth to timeout
• and even send Fibre Channel Loop Initialization Primitives (LIP) to specified hosts.

More can be read here: http://wiki.petroskoutoupis.com/index.php5?title=DrvAdm

I would like to announce a new disk management utility for Linux platforms. Specifically for the 2.6. 32+ kernels. It is called DrvAdm and is currently supported on Ubuntu Desktop/Server 10.04 and Red Hat ES 6 (to be released by end of 2010). Validation for Red Hat ES 6 was done on the second beta release.

You can read more about it on its wiki page or download it directly from its Sourceforge.net hosted project page. For the most part, DrvAdm supports the following features:

• Dynamically add / remove / update devices in the SCSI subsystem
• Reset the SCSI host, target, bus or all.
• Retrieve a list of all SCSI devices with detailed information
• Retrieve a list of all SCSI hosts with detailed information
• View the device’s partition table
• Retrieve the device’s geometry / size
• Modify device parametets (i.e. queue_depth, timeout, etc.)
• Send Loop Initialization Primitives (LIPs) to the Fibre Channel hosts