ram memory

Asked by Ampers

I am fairly new to the concept of RAM memory and have three questions.

1. I can upgrade my computer's memory to 4 gigs. How much memory will the 32-bit Ubuntu access?

2. Am I understanding 64-bit correctly? As I understand it, I can load in the Ubuntu 64-bit software and there are no benefits running normal software other than it can address more than a certain amount of RAM?

3. Is there any useful way one can use more than the maximum RAM using 32-bit software other than load the swap file into RAM?

I am only asking for short answers here with the intention of following up with my own research depending on which pointers I get.

Ampers.

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Tom
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Tiago Faria (gouki) said :
#1

Hi,

If you want to use 4GB of RAM, you'll have to use the ubuntu-server kernel flavour, since this kernel has PAE enabled. That, or you can recompile the kernel with that option active.

Since you said you wanted to "follow up with your own research" I won't say anything else. If you need help, feel free to ask.

Tiago

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Ampers (ampers) said :
#2

I am not asking for quite that. I want to know whether the normaal Ubuntu flavour is the same as Windows and only addresses 3GB to 3.5GB of memory as I am more interested in using the rest as a RAM disk for, perhaps, the swap file.

I really don't want to get involved with the 64-bit version or the Ubuntu Server kernal.

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Ufuk (ufukkilicaslan) said :
#3

Hello. If you want to use more of your RAM instead of using swap partition, it is possible. Since you have fairly good amount of RAM, you don't need to use swap when it is not needed. Linux uses free RAM to speed up the processes and increase the visible performance. You can do this:

Press ALT+F2 and run the command:

gksudo gedit /etc/sysctl.conf

add this line at the end of the file:

vm.swappiness=1

You can play with the 1 value, you can increase it if you feeld slow. But I don't think you will need it. You can also add another line:

vm.vfs_cache_pressure=50

And save the file, reboot the system for the changes. If you want to read about this, there is a nice article:

http://rudd-o.com/en/linux-and-free-software/tales-from-responsivenessland-why-linux-feels-slow-and-how-to-fix-that

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Best Tom (tom6) said :
#4

There seems to be a lot of misunderstanding.
https://help.ubuntu.com/community/SwapFaq

Crucially ...
The swap-file or in linux's case the swap partition is a storage area the Ram can temporarily use when it starts feeling a bit full.

But also ...
Basic Windows functions tend to be quite heavy on ram usage whereas linux's are far more efficient with it and so you'll find that Windows needs a lot more ram than linux even before you start opening applications. Similarly with standard apps - Internet Explorer is much heavier in it's use of ram whereas Firefox tends to be much lighter.

Windows files tend to suffer from being fragmented and the standard Windows defragmenters are seldom able to defragment system-files such as pagefile.sys whereas linux tends to keep the swap contiguous within a single dedicated partition so the Ram can read/write to it faster and more efficiently.

32bit versions of Windows are unable to deal with multi-core processors still? Linux had multi-processor support in 32bit versions from the start.

So to answer your specific questions
1. Don't bother to add more ram (unless you are keeping Windows) you're unlikely to ever need even 2Gb of Ram, even as a heavy gamer with HDTV on a 2nd monitor.

2. Incompatibility issues? I can't imagine that 64biit Windows will run all it's 32bit programs flawlessly. I thought you needed to get 64bit versions of programs?

3. ??

Sorry this has been a lot longer than you wanted
Hope this hasn't further muddied the waters
Regards from
Tom :)

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Ampers (ampers) said :
#5

As usual, your replies address my problems so well. :-)

Thanks for that, it is everything I was looking for and more. I checked with crucial.com for memory prices and learned that memory for my motyherboard was less than a tenner per gig. plus VAT so your reply has saved me £24. If we ever meet up, I'll buy you a pint or two. :-)

Ampers.

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Ampers (ampers) said :
#6

Thanks Tom, that solved my question.