set up pernament ramdisk in ubuntu to not using ram when is the ramdisk empty

Posted by robo on Super User See other posts from Super User or by robo
Published on 2012-12-06T23:01:21Z Indexed on 2012/12/06 23:06 UTC
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ubuntu

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hibernate

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ubuntu-12.04

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swap

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ramdisk

Hi I've got 8GB RAM on my laptop running Ubuntu 12.04. I added following record to /etc/fstab tmpfs /media/ramdisk tmpfs defaults,noatime,mode=1777 0 0

What exactly it means? I have tested that I can save 4GB to ram disk at most. Why exactly 4GB? Where did the computer get this number from?

And what happens when I don't use that ram disk for a while and when the directory /media/ramdisk is empty? Does it mean that my system can use whole 8GB ram?

And what happens when the system runs out of ram? Will the most rarely used things be moved to swap?

And should I turn of swap if I think my system will never need it? Will turning off the swap make my computer faster? And can I even remove the swap partition? And will the hibernation work correctly then?

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