"Merging" external SD memory with internal memory?

Hi everyone,

I'm totally new to Linux, so please forgive if the answer to my question is already on this board. I just don't know the right technical terms to do a decent search...

This weekend I bought an Aspire One with Linpus Linux. It has 16 GB memory "fixed" and I bought an extra 16 GB Ultra SD card for extra storage. When I inserted the card, some pop-up asked me some technical question which eventually resulted in the expanded 16 GB SD memory to be some kind of "merged" with the internal 16 GB, so ending up with a (virtually?) 32 GB system. I though this was pretty cool and happily explored my new 32 GB toy...

Naturally, I got extremely bored with the crippled Linpus installation within about two hours. Any OS that makes you perform tricks and jump through hoops to get things done doesn't deserve to live on any of my systems. Even the UNIX distribution on my iPhone is more advanced than this Linpus thing. :|

Anyhow... after a lot of reading I decided to install Ubuntu Remix 9.04 on it. This is all running pretty fine, apart from some annoying temporary "freezes" which turns my entire screen grey fora few seconds every few minutes, mostly when browsing the Internet.

My final question is this; how do I get Ubuntu to do to the same "trick" with the extra 16 GB memory, so the entire system will appear to have just one 32 GB drive? Is this some kind of program, is it some sort of virtual RAID system? Can it be done afterwards or do I needs to re-install Ubuntu (which I wouldn't mind to do at all to get to the 32 GB system again).

The original Linpus / Aspire manual only states that I should use the left-side expansion for this and use the right-side slot for "regular" memory card swapping, but for Ubuntu, the left- and right-side expansions just both act the same way, giving me an SD card on my desktop.

I hope my question was clear and will result in an evenly clear answer. Thanks for reading anyway.

 

Can't say for sure. But I think the "merging" trick is something that Acer's modded version of Linpus was uniquely set up to do. The 'Storage Expansion' slot being an Acer Aspire One-specific hardware feature... But I could be wrong.

I don't know how you would get another Linux OS to do the same thing. By the way, once you enable the "advanced mode" in Acer's Linpus distro - to access all of the software that's actually installed on the device and the package manager etc. - the whole OS becomes far more capable and satisfying to use.

 

Hi El Matarife,

I also had the feeling this "merging trick" was Aspire One / Linpus specific, therefore I tried to re-install Linpus from the DVD to see if I could find the program actually performing the "trick". Unfortunately the DVD must be damaged or something, because I was unable to install it in any way imaginable. I first tried it inside an emulator (Virtual PC on my Mac), but it wouldn't boot beyond the initial AspireOne logo. Then I tried the original DVD on an old Window laptop, same result. Finally I "burned" the DVD to USB using various tools and tried booting it on the emulator, Windows laptop and the Espire One itself. Every single time the same result. Got to the Aspire One loge with some empty progress bar below that would not go any further.

Think my only option is to just try to build some sort of fake or simulated RAID using the internal memory and the SD card... or maybe I should just accept the 16 GB internal "drive" and then somehow just move my home folder to the SD card.

While typing this reply I remember that the Linpus distribution reported the "merge" on every single reboot, so it MUST just have been some program running inside the distribution.

Well, thanks for the reply anyway, I'll just continue experimenting along. As long as there is nothing "really important" on my Aspire One, I can just keep on re-installing the entire thing over and over again. Luckily I've got about 4 spare/old USB sticks to experiment along with. Meybe I'll even try Windows, if that could ever run on my model anyways. (No real harddisk). :roll:

 

That's a real annoyance if your recovery CD/DVD doesn't seem to work. I'm sure if you contacted Acer they would ship you a freebie replacement. A short while ago an image of the recovery disc was actually made available as an online download:

http://macles.blogspot.com/2008/12/acer ... y-dvd.html

But unfortunately it was removed from the Acer FTP site - presumably due to bandwidth issues(?) - it was a pretty big file! But the image is still readily available on various bittorrent tracker sites if you do a Google search for "Acer Aspire One Recovery Image".

 

Hi Ruben

The Acer "trick" of merging the SSD with an SD card in the left hand slot is performed by software called Aufs. The "trick" merges 2 directories into one i.e. the directory on the SSD called /usr/home with the directory that holds any data on the SD card called /media/disk there bye creating one merged directory called /mnt/home. Depending what View you use within file manager you will see your (nearly) 32GB or will see SD/MMC drive (/media/disk directory).
In windows terms it is not like saying my C drive is now 16GB bigger as I have inserted an 16GB SD card.
Rather C drive is still its original size, I have added an SD card as drive E but I now have a software created unified file system contained in virtual drive F with the contents of C and E.
You may find some help on the Ubuntu forum but personally I have a difficulty in seeing any great advantage other than it sounds good sales talk that by adding a card in the LH slot you have Storage Expansion. What have you got if you add one to the RH slot?

You could also google aufs.

 

Interesting! I guess what the Aufs software does is more for the sake of enabling seamless file management between the 2 "drives" for the end user (which in itself is pretty handy). And its more about the perception of having one larger drive than the reality?

A question - can you install and run applications on the SD card as if it was part of the SSD - or can you only install apps on the actual SSD itself? I notice that once you start using an SD card in the "storage expansion" slot, any files you manually copy or save to the device automatically go onto the card - presumably to save room on the SSD for system and program files?

Having 2 card readers is quite a cool feature though - and I do like the way the software manages the swap-out of your storage expansion SD for you, if you want to insert a larger card (old card is in expansion slot, new card goes in RH slot, data is copied across, you eject both and move the new card into the storage slot). It doesn't sound fancy, but it does make it easy for the user to do - without you having to worry about accidentally buggering anything up!I appreciate things that are easy!