No swap in use even when RAM get fully allocated

[Azyx]

Hi.
I have system-monitor applet and kan follow CPU acyivity, RAM use, network, system load, swap and disj.

I have 1,7GB RAM to system, (0,3 to the grafic-card) and I have 2GB disk to awap,
When i run the flash-game FarmVille a lot of RAM get filled up, and if I run a long time and work much, my RAM get totally used by application (not only as cache and the desktop freeze, totally, so I have to ctrl+alt+F1 to open a terminal and start top and kill mozilla and then go back and open mozilla again.

What I now notice is that the swap don't at all are in use!!! and I think that can be the reason to why the desktop freeze.

I don't remember If I sometime turned of the swap or so...but I have no idea where I maybe turn it of.

I running Ubuntu 8.04 LTS

Thanks for any help

/Cheers

[louieb]

1st make sure swap is allocated and ready for use. Post the output of

free -m

[Azyx]

1st make sure swap is allocated and ready for use. Post the output of

free -m

Fist: when I run :
Azyx@intel:~$ swapon -s there is no outcome

and the outcome from free -m is:

total used free shared buffers cached
Mem: 1772 1202 570 0 16 265
-/+ buffers/cache: 920 851
Swap: 0 0 0

So the swap is tuned of. (can also have happen when i downgrade from 8.10 cos hardare problems..

I have an swap-partition when I look in Gparted.

[Azyx]

1st make sure swap is allocated and ready for use. Post the output of

free -m

I saw a swapon thing in Gparted (It was off) and activated the swap there. And now I get the outcome:

free -m
total used free shared buffers cached
Mem: 1772 1222 549 0 17 266
-/+ buffers/cache: 938 834
Swap: 2047 0 2047

PS. How do i wrap CODE?

[louieb]

Swap is not being turn on automatically. That is controlled by file /etc/fstab

Need 3 things :


sudo fdisk -l
sudo blkid -c /dev/null
and a listing of file /etc/fstab

Code tags are created by pressing the # (make sure your Ubuntu forums profile is set to use the advanced editor).

[Azyx]

It's little desturbing...
I don't have any swap in fstab. I don't know why..Can it be cos I have during installation maked a primary partition and not an logical? I don't find any mount-point ether in Gparted.

When I look at fstab on another computer I found something like his:

# swap was on /dev/sda5 during installation
UUID=76733465-aeb3-40dc-ba16-5526979e86c0 none swap sw 0 0

Can I use /dev/sda5 instead of UUID=76733465-aeb3-40dc-ba16-5526979e86c0 in fstab, or how do I find that long partition UUID for my partition? (I his computer It's sda1 but i take this as an example)

PS. I still not manage to aktivate Bold (B), Italic (I) or CODE (#) in this forum.Nothing happent when I maked the text and click on symbols up when I reply,

[louieb]

you find the UUID with the blkid command.

and yes you can use /dev/sda5 or what ever your swap partition is.

I've used both - the UUID is better if you ever want to add another hdd.

You are correct - select the text you want to bold or put in a code block before pressing the button - don't know why it not working for you.

[Azyx]

you find the UUID with the blkid command.

and yes you can use /dev/sda5 or what ever your swap partition is.

I've used both - the UUID is better if you ever want to add another hdd.

You are correct - select the text you want to bold or put in a code block before pressing the button - don't know why it not working for you.

So UUID is not only there to complicate things ;)

Now I get this:


Azyx@intel:~$ swapon -s
Filename Type Size Used Priority
/dev/sda1 partition 2096440 0 -1
Azyx@intel:~$ free -m
total used free shared buffers cached
Mem: 1772 976 796 0 24 452
-/+ buffers/cache: 498 1273
Swap: 2047 0 2047

On the page:
http://www.linux.com/news/software/applications/8208-all-about-linux-swap-space

They say that fstab shuold look like this:


/swapfile none swap sw 0 0

but on Ubuntu 9,04 fstab looks like this:


UUID=76733465-aeb3-40dc-ba16-5526979e86c0 none swap sw 0 0

The row don't beguinn with /swap

Will see how it should be on Ubuntu 8.04. I have not still manage to fill up the RAM becourse I reboot.

Cheers and thank for all help :)

PS. It seems like a problem with mozilla cos it work with Chrome with code and stuff. I run mozilla 3.6 on Ubuntu 8.04.. maybe the backporting don't fully work?

[Azyx]

It worked :)
When I came up to above 90% RAM-use the swap-space begin to be used :)

Thanx again. I'm little unused to trix with terminal and so cos Ubuntu almost always just work :) I have not have need for more virtual memory until I begin to play that f*ckn FarmVille ;) that really eat memory..

[m0nstersnatch]

Hello,

I think I have a similar problem. I have 4GB RAM but the system performs poorly and now that I have read your post I think it has something to do with the swap.


/etc/fstab
# / was on /dev/sda1 during installation
UUID=2ac2d1b6-6b1c-44e1-ae8f-44a5616217d1 / ext4 relatime,errors=remount-ro 0 1
# swap was on /dev/sda2 during installation
UUID=2b145d3d-df5f-4779-bab0-2e033dc0c604 none swap sw 0 0
/mnt/512Mb.swap none swap sw 0 0
/dev/scd0 /media/cdrom0 udf,iso9660 user,noauto,exec,utf8 0 0
/dev/fd0 /media/floppy0 auto rw,user,noauto,exec,utf8 0 0
/dev/sda3 /media/MRBIG ext4 users,user 0 2
sudo blkid -c /dev/null
/dev/sda1: UUID="2ac2d1b6-6b1c-44e1-ae8f-44a5616217d1" TYPE="ext4"
/dev/sda2: UUID="2b145d3d-df5f-4779-bab0-2e033dc0c604" TYPE="swap"
/dev/sda3: LABEL="MRBIG" UUID="0586fac1-aa46-4b26-a19e-436b577521f0" TYPE="ext4"
sudo fdisk -l
Device Boot Start End Blocks Id System
/dev/sda1 * 1 2745 22049181 83 Linux
/dev/sda2 2746 3060 2530237+ 82 Linux swap / Solaris
/dev/sda3 3061 38913 287989222+ 83 Linux
free -l
total used free shared buffers cached
Mem: 3614012 1796944 1817068 0 28668 1239988
Low: 853876 147476 706400
High: 2760136 1649468 1110668
-/+ buffers/cache: 528288 3085724
Swap: 3054508 0 3054508As you can see the swap is not beeing used, but there is a /mnt/512Mb.swap which I cannot recall making. What is this all about ?

Thanks !

[Azyx]

Hello,

I think I have a similar problem. I have 4GB RAM but the system performs poorly and now that I have read your post I think it has something to do with the swap.

As you can see the swap is not beeing used, but there is a /mnt/512Mb.swap which I cannot recall making. What is this all about ?

Thanks !



free -l
total used free shared buffers cached
Mem: 3614012 1796944 1817068 0 28668 1239988

Seems that you have 1817068 byte free in RAM, so there are no need to start use the slower swap-memory i think? Open up a lot of web-pages so you use up all RAM and see if the swap start to be used.
/Cheers

[grahammechanical]

Hi m0stersnatch

Regarding this comment of yours


but there is a /mnt/512Mb.swap which I cannot recall making. What is this all about ?

The installation process created this swap partition. The size can be changed but you are not given the choice of doing without one.

Regards.