You are not logged in.

#1 2004-12-30 13:25:20

giddygiddyBA
Member
From: Montreal
Registered: 2004-12-30
Posts: 66

system reads RAM inconsistently

this one has bugged me for a while

both torsmo and gkrellm read RAM to be around  100M/723M

                               BUT

'free -m' reads a whopping 713M/723M

there's no way im using this much RAM...

just a minor problem, but SWAP is being used when it shouldnt be, causing the system to slow down.

on a side note, what commands do torsmo and gkrellm use to get RAM info?

Offline

#2 2004-12-30 13:34:33

dp
Member
From: Zürich, Switzerland
Registered: 2003-05-27
Posts: 3,363
Website

Re: system reads RAM inconsistently

i have no idea ... but you can e.g. have a look at

lsof | grep mem

for some info


The impossible missions are the only ones which succeed.

Offline

#3 2004-12-30 16:26:12

iBertus
Member
From: Greenville, NC
Registered: 2004-11-04
Posts: 2,228

Re: system reads RAM inconsistently

You've probably just hit the big "the system grabs up all memory for file buffers and then reallocateds it as needed" property. The linux kernel will most of the memory of the system for file cache until something else requests it. Some apps display the memory uses minus file cache... but some will display the current total memory usage (including file cache) which is sort of misleading.

For example this shows that i've got 148724K free but not counting buffers it's 594952K w/ only 179284K used by programs:

             total                 used       free     shared    buffers     cached
Mem:        774236     625512     148724          0     154456     291772
-/+ buffers/cache:     179284     594952
Swap:      1502068          0        1502068

Offline

#4 2004-12-30 17:33:57

dp
Member
From: Zürich, Switzerland
Registered: 2003-05-27
Posts: 3,363
Website

Re: system reads RAM inconsistently

iBertus wrote:

You've probably just hit the big "the system grabs up all memory for file buffers and then reallocateds it as needed" property. The linux kernel will most of the memory of the system for file cache until something else requests it. Some apps display the memory uses minus file cache... but some will display the current total memory usage (including file cache) which is sort of misleading.

For example this shows that i've got 148724K free but not counting buffers it's 594952K w/ only 179284K used by programs:

             total                 used       free     shared    buffers     cached
Mem:        774236     625512     148724          0     154456     291772
-/+ buffers/cache:     179284     594952
Swap:      1502068          0        1502068

exactly ... but this does not explain the swapping he/she spoke about


The impossible missions are the only ones which succeed.

Offline

#5 2004-12-31 03:47:03

giddygiddyBA
Member
From: Montreal
Registered: 2004-12-30
Posts: 66

Re: system reads RAM inconsistently

ahhhh, yes it seems to make sense now

those apps i mentioned are just using

RAM = used - buffers - cached (- shared? ? )

(12:43||~)$ free -m
             total       used       free     shared    buffers     cached
Mem:         722        533        189          0         47        292
-/+ buffers/cache:        193        529
Swap:        39          0         39

im missing alot of my bigger apps, ill try to show SWAP usage later

thanks for the help

Offline

#6 2004-12-31 05:53:37

neotuli
Lazy Developer
From: San Francisco, CA
Registered: 2004-07-06
Posts: 1,201
Website

Re: system reads RAM inconsistently

If you want it to swap less, you could try adjusting swappiness.

cat /proc/sys/vm/swappiness

That'll give you your current value.

To adjust, just echo in a new value and see what the results are.

Further discussion on that control can be found at:
http://kerneltrap.org/node/3000
you might also try the kernel documentation: http://www.kernelhq.cc/browse-files.py? … 39&path=82

Good Luck!


The suggestion box only accepts patches.

Offline

#7 2005-01-01 04:31:12

giddygiddyBA
Member
From: Montreal
Registered: 2004-12-30
Posts: 66

Re: system reads RAM inconsistently

great article neotuli

learn a new thing every day

thanks for the help, i think i have my head around this one finally

happy new year

Offline

#8 2005-01-01 15:27:59

oscar
Member
From: Linköping, Sweden
Registered: 2004-08-13
Posts: 457

Re: system reads RAM inconsistently

concerning the swappiness - some kernel sources (like gentoo-sources) includes a patch that takes care of the swapping rate automagically (;)) - but I don't think that patch is included in the arch-source smile


To err is human... to really foul up requires the root password.

Offline

Board footer

Powered by FluxBB