ram usage and tmpfs

iBertus · 2006-01-25 05:42:51

I just dropped a 2GB dual channel kit in this box and now I'm not sure what to do now. I'm not going to upgrade anything else until I dive into a 64-bit system next year. I'll keep this box around as a server or backup then, but now I'm trying to find something to do with all that memory. I use lots of GIS apps and they love the extra memory but I've not noticed any benefit to my regular desktop activities.

edit: changed title to be more descriptive - phrakture

Cerebral · 2006-01-25 05:52:53

Now, you take the memory that used to be in the machine, and send it to me.

Uh.... start burning DVDs at 1000x? Spawn a jillion xterms? Or firefox with 10 tabs?

I really don't know what you'd do specifically to max out ram usage with 2GB of the stuff considering I've only ever had 512 MB.

elasticdog · 2006-01-25 05:56:12

I too recently upgraded to a 2GB dual-channel setup (up from 512MB) and also haven't noticed a huge change. I do vaguely remember reading somewhere that there was a setting where you could force the entire kernel to remain in memory at all times which could speed stuff up...am I on crack? Come to think of it, that might have been a Windows related tweak for users with large amounts of memory, but I could be wrong...

Does anyone know of any specific things you can do to have your system take advantage of large amounts of ram?

iphitus · 2006-01-25 05:59:46

Games

If you leave your computer on, use your ram as hard drive space. Before I got my second hard drive, I used to use my ram for some kernel patching stuff.

Use it as space for makepkg'ing.

I have my desktop setup and mounted in ram. I have my downloads set to desktop, so when I boot, my 'download folder' is cleared.

iphitus

tomk · 2006-01-25 07:50:24

Cerebral wrote:

firefox with 10 tabs?

(Counting .... please wait...)

Yes, I'm using ff with 10 tabs right now - with 384MB RAM.

iphitus · 2006-01-25 08:21:16

tomk wrote:

Cerebral wrote:
firefox with 10 tabs?
(Counting .... please wait...)
Yes, I'm using ff with 10 tabs right now - with 384MB RAM.

I think he meant one tab with a poorly written flash app

iphitus

tomk · 2006-01-25 10:45:11

- Yeah, I hear you. One of those, and I'm screwed!

Cerebral · 2006-01-25 12:39:37

tomk wrote:

Cerebral wrote:
firefox with 10 tabs?
(Counting .... please wait...)
Yes, I'm using ff with 10 tabs right now - with 384MB RAM.

I was being "cute", I use firefox myself and currently have 12 tabs open on my measly 512.

But yeah, a portion sectioned off as a ram disk would be pretty useful, I'd imagine.

iphitus · 2006-01-25 15:07:54

Cerebral wrote:

tomk wrote:
Cerebral wrote:
firefox with 10 tabs?
(Counting .... please wait...)
Yes, I'm using ff with 10 tabs right now - with 384MB RAM.
I was being "cute", I use firefox myself and currently have 12 tabs open on my measly 512.
But yeah, a portion sectioned off as a ram disk would be pretty useful, I'd imagine.

Aye, Arch used to have /tmp mounted as a tmpfs disk in ram. the fstab line is:

tmpfs    /tmp    tmpfs     defaults   0 0

So if you want to make your own on the fly...

mount tmpfs /home/bob/directory -t tmpfs

iphitus

Moo-Crumpus · 2006-01-25 15:38:17

http://bbs.archlinux.org/viewtopic.php?t=16152

elasticdog · 2006-01-25 17:48:30

Moo-Crumpus wrote:

http://bbs.archlinux.org/viewtopic.php?t=16152

I don't think that anyone has asked stupid questions...perhaps the thread should be moved to Off-Topic, but I think people's responses have been informative.

Moo-Crumpus · 2006-01-25 20:11:17

I am just tired of not informative topics. You'll have to open each of em to find out if it is about a problem, a solution, something I take care of or something I try to ignore. I am tired of it, and it is not a kind behaviour - afaik.

"So what" is ... bah.

iphitus · 2006-01-25 23:26:50

A new title might be good, but this does have information in it, like my tmpfs suggestions.

iBertus · 2006-01-26 14:33:43

iphitus wrote:

A new title might be good, but this does have information in it, like my tmpfs suggestions.

I like this suggestion for using part for a ramdisk very much and will give it a try.

I'll leave the move to OT up to the mods, but I'm not of the opinion that this belongs there. I'm looking for ways to improve my workstation setup now that I have more memory installed which is a legitimate topic.

AndyRTR · 2006-01-26 16:25:54

Just a memory related question: I'm running Arch64 with a DualCore Opteron. I know that there are still several kernel issues with these cpus on the KML. But watch this:

[root@workstation64 andyrtr]# free -m
             total       used       free     shared    buffers     cached
Mem:          3017       2989         27          0        786        322
-/+ buffers/cache:       1880       1137
Swap:          235          0        235

top - 17:16:54 up 19:40,  1 user,  load average: 2.08, 2.18, 2.22
Tasks: 129 total,   3 running, 126 sleeping,   0 stopped,   0 zombie
Cpu(s):  9.5% us,  2.5% sy, 87.7% ni,  0.2% id,  0.0% wa,  0.2% hi,  0.0% si
Mem:   3090156k total,  3061460k used,    28696k free,   805560k buffers
Swap:   240932k total,        0k used,   240932k free,   330244k cached

  PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
 1929 andyrtr   15   0  326m 142m  21m S    1  4.7   3:21.37 firefox-bin
 1965 andyrtr   15   0  345m 133m  23m S    0  4.4   4:55.81 thunderbird-bin
 1746 root      16   0  195m 106m  19m S    9  3.5  24:59.94 X
27707 andyrtr   39  19 45316  40m 1264 R   96  1.3  53:06.66 setiathome_SSE-
28002 andyrtr   39  19 45316  40m 1264 R   80  1.3  31:53.75 setiathome_SSE-
 1914 andyrtr   15   0  113m  38m 9572 S    0  1.3   7:19.17 xfce4-panel
 2375 andyrtr   16   0  134m  38m  23m S    0  1.3   0:06.65 krusader
 3041 andyrtr   15   0  248m  36m  25m S    4  1.2  38:14.11 klear
 2013 andyrtr   15   0 78084  23m 8356 S   10  0.8   0:16.45 terminal
 1990 andyrtr   15   0  117m  18m  11m S    0  0.6   0:14.25 gaim
 2406 andyrtr   16   0 97120  15m  10m S    0  0.5   0:00.78 kio_uiserver
 1984 andyrtr   15   0 72780  14m 8504 S    0  0.5   0:10.00 xchat
 3886 andyrtr   16   0  109m  13m 8176 S    0  0.4   0:00.07 knotify
 1907 andyrtr   15   0 94936  13m 7284 S    0  0.4   0:23.85 xfce-mcs-manage
 2005 andyrtr   15   0 88040  12m 8596 S    0  0.4   0:21.91 kded
 3764 andyrtr   15   0  248m  11m  536 S    0  0.4   0:00.00 klear
 1903 andyrtr   15   0 60916  11m 7228 S    0  0.4   0:26.41 xfce4-session
 2371 andyrtr   16   0 84468  11m 7444 S    0  0.4   0:00.15 kaccess
 1943 andyrtr   16   0 69488   9m 7164 S    0  0.3   0:09.02 gkrellm
 1910 andyrtr   15   0 56832 9.8m 6552 S    0  0.3   0:31.99 xfwm4
 2003 andyrtr   16   0 80248 9964 7084 S    0  0.3   0:00.05 klauncher
 1912 andyrtr   15   0 65372 9728 6012 S    0  0.3   0:25.02 xfdesktop
 1998 andyrtr   16   0 79316 9700 6280 S    0  0.3   0:00.08 kdeinit
 5591 andyrtr   16   0 81944 9500 5824 S    0  0.3   0:00.03 kio_file
 2001 andyrtr   16   0 77376 7716 5132 S    0  0.2   0:00.12 dcopserver
19838 root      16   0 78320 6116 3136 S    0  0.2   0:00.19 httpd
 1568 root      16   0 11752 4652 3444 S    0  0.2   0:00.07 ntpd
 2022 andyrtr   16   0 13232 4492 1416 S    0  0.1   0:05.11 boinc_4.19.3_x8
19840 nobody    18   0 78320 3932  936 S    0  0.1   0:00.00 httpd
19841 nobody    18   0 78320 3916  920 S    0  0.1   0:00.00 httpd
19842 nobody    20   0 78320 3916  920 S    0  0.1   0:00.00 httpd
19843 nobody    20   0 78320 3916  920 S    0  0.1   0:00.00 httpd
19844 nobody    20   0 78320 3916  920 S    0  0.1   0:00.00 httpd
 1933 andyrtr   16   0 19212 2788 1936 S    0  0.1   0:00.03 gconfd-2
 1892 andyrtr   15   0 23180 2472 1844 S    0  0.1   0:13.77 xscreensaver
 3801 andyrtr   15   0 11144 2188 1420 S    0  0.1   0:00.14 mc
 1666 andyrtr   16   0  9520 2160  844 S    0  0.1   0:02.93 famd
 2031 andyrtr   16   0 10776 2104 1476 S    0  0.1   0:00.03 bash
 2029 andyrtr   16   0 10772 2084 1492 S    0  0.1   0:00.01 bash
 2030 andyrtr   15   0 10776 2080 1484 S    0  0.1   0:00.01 bash
 2418 root      16   0 10516 2072 1476 S    0  0.1   0:00.03 bash
 2015 andyrtr   16   0 10772 2068 1480 S    0  0.1   0:00.00 bash
 2422 root      15   0 10080 2056 1388 S    0  0.1   0:00.04 mc
 3803 andyrtr   16   0 10780 2052 1448 S    0  0.1   0:00.08 bash
 2424 root      17   0 10516 2048 1448 S    0  0.1   0:00.00 bash
 2032 andyrtr   15   0 10776 2032 1436 S    0  0.1   0:00.00 bash
 2421 root      15   0 10516 2032 1436 S    0  0.1   0:00.00 bash

free tells me that 1880MB are used but even when I count all processes there's a huge gap. So where's my memory gone?

I guess it's kernel related because swap is never used and sometimes it drops a few hundred MBs and then suddenly increases again. Is there a way to locate the memory usage of each kernel module?

Any idea how to locate that?

Ah, and this is only in Arch64 not in (32bit) ArchLinux although the kernel uses almost the same config but cpu related stuff.

pikass · 2006-01-26 16:36:36

That could be everything, closed apps for example. The data could be needed at a later time and having at least something loaded is more usefull then free mem.

iBertus · 2006-01-26 20:29:16

pikass wrote:

That could be everything, closed apps for example. The data could be needed at a later time and having at least something loaded is more usefull then free mem.

Yeah, it's probably file cache or similar at work. If so, then it'll be freed when needed by any processes.

AndyRTR · 2006-01-26 20:36:22

Maybe. But this behavior is only in 64bit environment. And SingleCore CPU users don't have it.

Mr Green · 2007-12-12 19:21:01

interesting .....

skottish · 2007-12-12 19:47:34

If you have too much memory:

mplayer dvd://1 -dumpstream -dumpfile out.mpg

Your memory will love you.

Last edited by skottish (2007-12-12 19:48:31)

Arch Linux

#1 2006-01-25 05:42:51

ram usage and tmpfs

#2 2006-01-25 05:52:53

Re: ram usage and tmpfs

#3 2006-01-25 05:56:12

Re: ram usage and tmpfs

#4 2006-01-25 05:59:46

Re: ram usage and tmpfs

#5 2006-01-25 07:50:24

Re: ram usage and tmpfs

#6 2006-01-25 08:21:16

Re: ram usage and tmpfs

#7 2006-01-25 10:45:11

Re: ram usage and tmpfs

#8 2006-01-25 12:39:37

Re: ram usage and tmpfs

#9 2006-01-25 15:07:54

Re: ram usage and tmpfs

#10 2006-01-25 15:38:17

Re: ram usage and tmpfs

#11 2006-01-25 17:48:30

Re: ram usage and tmpfs

#12 2006-01-25 20:11:17

Re: ram usage and tmpfs

#13 2006-01-25 23:26:50

Re: ram usage and tmpfs

#14 2006-01-26 14:33:43

Re: ram usage and tmpfs

#15 2006-01-26 16:25:54

Re: ram usage and tmpfs

#16 2006-01-26 16:36:36

Re: ram usage and tmpfs

#17 2006-01-26 20:29:16

Re: ram usage and tmpfs

#18 2006-01-26 20:36:22

Re: ram usage and tmpfs

#19 2007-12-12 19:21:01

Re: ram usage and tmpfs

#20 2007-12-12 19:47:34

Re: ram usage and tmpfs

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