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
Read the original article Hit count: 450

Filed under:

ubuntu

|

hibernate

|

ubuntu-12.04

|

swap

|

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?

© Super User or respective owner

Related posts about ubuntu

Cannot update, apt-get cannot fetch index files

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
I have a fresh install of Ubuntu 11.10 from the iso 'ubuntu-11.10-desktop-amd64.iso'. I installed this in VMWare Fusion 4.1.1 running on OSX 10.7.3. When setting up the VM, I allowed easy install to take care of creating my user and installing VMWare tools. No problems during installation, everything… >>> More
'sudo apt-get update' error on Ubuntu 12.04

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
When I type in 'sudo apt-get update' I get this mohd-arafat-hossain@TUD:~$ sudo apt-get update [sudo] password for mohd-arafat-hossain: Ign http://bd.archive.ubuntu.com precise InRelease Ign http://bd.archive.ubuntu.com precise-updates InRelease Ign http://bd.archive.ubuntu… >>> More
Opening Skype, Opera, OpenOffice logs me off

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
Whats common among Skype, Opera, OpenOffice in Ubuntu ? Whenever I open these applications I get logged off and shows back me the login screen. This started happening since the 10.10 upgrade. Forgot to mention : Yes, its x64.Each time I open these applications, the UI shows and then crashes. I… >>> More
Update information outdated

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
I have a warning triangle that my update information is outdated, the last update was 12 days ago. I use Ubuntu 11.10. A run of sudo apt-get update produces the following output: Ign http://ppa.launchpad.net oneiric InRelease Ign http://de.archive.ubuntu.com oneiric InRelease … >>> More
ubuntu/apt-get update said "Failed to Fetch http:// .... 404 not found"

as seen on Server Fault - Search for 'Server Fault'
Hi all, I'm trying to run apt-get update on ubuntu 9.10 I've configured my proxy server and I can access the internet without any problem: /etc/apt# wget "http://www.google.com" Resolving (...) Proxy request sent, awaiting response... 200 OK Length: 292 [text/html] Saving to: `index.html' 100%[=================================================================================================================================>]… >>> More

Related posts about hibernate

Hibernate unable to instantiate default tuplizer - cannot find getter

as seen on Stack Overflow - Search for 'Stack Overflow'
I'm trying to use Hibernate to persist a class that looks like this: public class Item implements Serializable, Comparable<Item> { // Item id private Integer id; // Description of item in inventory private String description; // Number of items described by this inventory item private int… >>> More
Hibernate + PostgreSQL : relation does not exist - SQL Error: 0, SQLState: 42P01

as seen on Stack Overflow - Search for 'Stack Overflow'
Hello, I am having some problems trying to work with PostgreSQL and Hibernate, more specifically, the issue mentioned in the title. I've been searching the net for a few hours now but none of the found solutions worked for me. I am using Eclipse Java EE IDE for Web Developers. Build id: 20090920-1017… >>> More
Problem connecting to Hsqldb via Hibernate when running a Eclipse GWT project.

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi, I'm trying to run a simple GWT project where I'm trying to do a simple persitence via hibernate to a HSQLDB database. The database I'm using I have been using for at least 2 years with several osgi applications without any problems. So all I done is reused the same configuration and added a simple… >>> More
Hibernate : load and

as seen on Stack Overflow - Search for 'Stack Overflow'
According to the tutorial : http://jpa.ezhibernate.com/Javacode/learn.jsp?tutorial=27hibernateloadvshibernateget, If you initialize a JavaBean instance with a load method call, you can only access the properties of that JavaBean, for the first time, within the transactional context in which it… >>> More
Hibernate Exception, what wrong ? [[Exception in thread "main" org.hibernate.InvalidMappingException

as seen on Stack Overflow - Search for 'Stack Overflow'
I use netbean 6.7.1 to write "hello world" witch hibernate, but I get some errors, plz help me, thank you very much. my exception init: deps-module-jar: deps-ear-jar: deps-jar: Copying 1 file to F:\Documents and Settings\My Dropbox\DropboxNetBeanProjects\loginspring\build\web\WEB-INF\classes compile-single: run-main: Oct… >>> More