A thumb drive is a small storage device that is a little larger than a key that contains a flash chip and a micro-controller. These devices range in size from about 16MB to 1GB. The great thing about most of these devices is that they require minimal drivers that come with all modern OSes. Even Linux has the base support for these drives in the standard kernel tree. They bring new meaning to Plug-and-Play and hopefully will usher in the end of the floppy disk. With the right BIOS, USB thumb drives can even be booted off of. This can be great for rescue devices or for a quick BIOS flash without a floppy.

Our thumb drive is manufactured by Crucial Technology and goes by the name of Gizmo!. It is a USB 1.1 device which can operate at a maximum of 12Mbps (megabits per second) or 1.5MBps (megabytes per second). The Gizmo! drive comes in 64MB, 128MB, and 256MB sizes. As shown in the photo above, the drive comes with a handy wrist strap and folded operating manual which will help you get the drive going under most versions of Microsoft Windows and MacOS 9.1 and up.

Getting the Gizmo! up and running was extremely easy and only required a kernel recompile under Gentoo. Most distributions that come with pre-compiled kernels won't even need this much work. All that is required for operation is the proper USB drivers for your motherboard, the USB mass storage driver, and VFAT filesystem support if you plan to use it with other OSes. For the USB mass storage driver to function, you will also need to enable SCSI support with SCSI disk support and SCSI generic support. Once we recompiled the kernel with these options, all that we needed to do was to add a line to our /etc/fstab file so that mounting the drive would be convenient. Here's the line we added:

/dev/sdb1     /mnt/usbdrive     auto     noauto,user     0     0

In this line, the drive is our second SCSI drive and we plan to mount it to the /mnt/usbdrive directory. We also have mount auto-detecting the filesystem type and we allow users to mount the device with default mount options. Now with a simple call to mount /dev/usbdrive, the drive can be mounted and ready to go.

Upon inserting the drive into a vacant USB port, you will see the following message in your logs or by typing dmesg:

hub.c: new USB device 00:1d.1-1, assigned address 2
scsi3 : SCSI emulation for USB Mass Storage devices
  Vendor: CRUCIAL   Model: USB DRIVE         Rev: 1.10
  Type:   Direct-Access                      ANSI SCSI revision: 02
Attached scsi removable disk sdb at scsi3, channel 0, id 0, lun 0
SCSI device sdb: 125952 512-byte hdwr sectors (64 MB)
sdb: Write Protect is off
 /dev/scsi/host3/bus0/target0/lun0: p1
WARNING: USB Mass Storage data integrity not assured
USB Mass Storage device found at 2

This message will tell you which SCSI device it is (sda, sdb, …) and how big the device is. As you can see from our output, we have a 64MB Gizmo! inserted as SCSI drive sdb. The line WARNING: USB Mass Storage data integrity not assured is simply stating that if you pull the plug on the drive without unmounting it, you could lose your data. This is important as Linux will cache data before writing to the disk. If you yank it without unmounting it, you could have data that has not been written yet.

The next question we had was about the performance of the drive. Being a USB 1.1 device we weren't expecting anything phenomenal, but we did want to make sure that we could perform normal tasks off of the drive without issue. In measuring driver performance we decided first to write a file of known size with an immediate unmount to write it and then to cat the same file to /dev/null and record the times. The file we used was a movie trailer that was exactly 34,266,862 bytes. To write the file it took an average of 50.803 seconds and to read the file it took an average of 53.357 seconds. The yields about 658 KB/s write speed and about 627 KB/s read speed. For a second opinion we turned to hdparm -t /dev/sdb which returned a read speed of 809.49 KB/s for a much smaller 4MB piece of data. Either way, that's not too slow for something that is designed to take the place of an incredibly slow floppy drive. At that speed we were even able to watch the video directly from the key drive without a glitch. The only time that the speed would really get annoying is if you bought one of the larger versions and planned on writing the entire drive at once on a regular basis. Around a four minute write for the 256MB drive would be a little time consuming.

One concern for many will be how well the drive holds up if carried around in a pocket with keys, cell phones, and other such bulky and potentially damaging items. The best way we found to test this abuse was by actually doing just that. I've been carrying this around in my pocket now for around four months on and off and it's still in one piece minus a small plastic clip that was attached to the wrist strap. The clip was a minor casualty as the rest of the drive has held up amazing well without barely a scratch. I've exposed it to many writes, reads, plugs, and unplugs and it still works like a champ. In fact, for the the past several articles, I have even worked off of this drive.

As far as long term usage and reliability is concerned we highly recommend this drive. The speed is so-so though so you may need to be patient if large writes are in your future for a portable device. The price of the Gizmo!s are only $33.99, $51.99, and $79.99 for the 64MB, 128MB, and 256MB drives respectively. Also, if you spend over $35 or more at Crucial, you'll get free 2-day shipping in the contiguous US. Not a bad deal for what you get. We see these drives as the future of quick and easy portable storage and Crucial has a great solution. The only thing that may hold you back would be faster USB 2.0 versions of these drives but at these prices you can probably just buy another one later. For a great product that works well with Linux, Crucial's Gizmo! drive takes home the Works with Linux Certification.

documented on: 2005.12.19