How to: ReadyBoost with Ubuntu Linux

[Treviño]

I think that users of PCs/Notebooks with flash-readers included could have a better use of their (generally) few used ports

I knew this fact, but unfortunately I can't apply... (and btw I've 1280mb of ram )

[max.durden]

May the ram be with you

[blue_Sphere]

Hi everybody,
by following this little tutorial you'll be able to use a USB pen prive as an additional swap. As a result, the pen drive will be used in the same way windows Vista does through the ReadyBoost functionality.

Instructions are very simple:

1) plug the pen drive in your usb connector;
2) if ubuntu automount the device (usually in /media/usbdisk), umount the device (ie., sudo umount /media/usbdisk);
3) sudo mkswap /dev/sda1 (assuming /dev/sda1 is the correct device for the connected usb device)
4) sudo swapon -p 32767 /dev/sda1

... and you are in!

do a "cat /proc/swaps" to check if everything is ok; on my laptop I get the following output:

Filename Type Size Used Priority
/dev/hda4 partition 2353512 116 -1 (standard HD swap partition)
/dev/sda1 partition 1981928 123900 32767 ("ReadyBoost"-style pen drive)

Quite obviously, performances are not the same as with real additional ram; however, I feel REAL gain in speed while using eclipse+tomcat+mysql for development on my laptop (which is equipped with just 512MB ram).

Possibly, a simple bash-script can be developed to automate the few steps...

Happy coding!

Max

Hrm reading this and knowing a little about windows paging I have some questions.

1. Data that is stored on swap is sometimes critical data, if the drive is removed the system will crash, corrupt files, etc. For this reason Vista makes a duplicate copy on the hard drive as well. Is this the same as linux?

2. The number of times flash can be rewritten is limited, we all know this, BUT according to Vista the readyboost system allows flash to last for ten years or even more. Is this true with Linux?

3. I know that programs like "virtual drive" for xp allow you to actually put the swap onto your ram if you have enough. Now this might sound excessive since swap is supposed to be an extension of ram, but the speed increase is phenomenal. Is this possible in linux? (or if linux actually makes efficient use of my ram I will cry tears of joy)

(Info on readyboost taken from here http://blogs.msdn.com/tomarcher/arch...02/615199.aspx)

I am currently running a turion 64 (2.4ghz) with 2gb of ram.

Thanks
-Blue

[max.durden]

Well, I am absolutely not an expert of linux swap management, but I will try to give you some answers while hoping that a "swap guru" will join the thread...

So

1) if you swapoff the usb drive, the system will start to use standard hd swap (assuming it is has been activated during the boot sequence). You can try this by monitoring "/proc/swaps" after having issued a swapoff /dev/sda1 command (I have not yet tried "brute force" unplug of the usb drive, however...);

2)I suspect it to be marketing ****...

3) simply turn off all your swap partitions

Please, let me now if you manage to get more info on the matter... It turns out to be very interesting to me, thanks

Bye
Max

[insane_alien]

just to add to this(although its completely pointless in this day of flashdisks by the dozen) it also works for a floppydrive

long story short, i was bored, i was browsing and i wanted to find a use for this floppy drive.

not so great performance though.

[shingalated]

Why would you need this in linux??
I have 768 MB of ram, and my computer hardly touches the swap file.

[insane_alien]

you don't it just proves that we can do anything MS can and have been able to for a long time. its just that we don't even need to do it that makes us so awesome

[shizeon]

From what I read, Vista's readyboost isn't making use of the flash drive for swap. It is using it as a disk cache for frequently accessed files. There is a difference if I understand this all correctly. A (slightly stretched) example would be if a program needs to open a specific image over and over again. If I was running vista, the program would automatically make use of the disk cache provided by readyboost and load it directly from flash. Placing the swap file on flash wouldn't provide any speed up here.

Am I wrong?

Found some details on how it is implemented at: http://blogs.msdn.com/tomarcher/arch...02/615199.aspx

Question is, can we do something similar on Linux to transparently cache disk access?

Nice tip though, still going to give this how-to a try on my low ram systems that swap frequently!

Thanks!
- Sean

[blue_Sphere]

From what I read, Vista's readyboost isn't making use of the flash drive for swap. It is using it as a disk cache for frequently accessed files. There is a difference if I understand this all correctly. A (slightly stretched) example would be if a program needs to open a specific image over and over again. If I was running vista, the program would automatically make use of the disk cache provided by readyboost and load it directly from flash. Placing the swap file on flash wouldn't provide any speed up here.

Am I wrong?

Found some details on how it is implemented at: http://blogs.msdn.com/tomarcher/arch...02/615199.aspx

Question is, can we do something similar on Linux to transparently cache disk access?

Nice tip though, still going to give this how-to a try on my low ram systems that swap frequently!

Thanks!
- Sean

Hrm I am interested in this as well...

[andb]

Ive got a wonderfully functional Edgy machine with 512MB memory. My Vista work laptop has 3GB, and its almost as fast.

Question - Concidering that memory management is done right in Linux, who needs such an problem-ridden solution?

MS has put a lot of work into their solution. If Linux kernel swap management could recognize what is not written to often then it might work. But why add unneeded functionality to the kernel? The more stuff, the more likely you are to have bugs. And this would really have to be a kernel level solution.

I have a 4 GB USB key on my vista machine now, and yes, it runs geat. But its still not faster than my 512MB P4 2.6ghz Edgy machine.

ReadyBoost is a great marketing ploy. But not appropriate in Linux. But if you think so, maybe you can also work on a way to seamlessly integrate the great MS Agents into your Linux desktop, too!