Subject: Re: explaining TOP memory output
To: None <netbsd-users@NetBSD.org>
From: Michael Parson <mparson@bl.org>
List: netbsd-users
Date: 07/13/2006 13:10:57
On Thu, Jul 13, 2006 at 12:25:05PM -0500, Przemys?aw Pawe?czyk wrote:
> Hi,
>
> I've come from Debian world. I used to run Opera, Sylpheed, and Tea
> editor. Now I use Deer Park (it has smaller footprint than Firefox,
> hasn't it?), Sylpheed, and Nedit. My system is very modest: Celeron
> 400, 128 MB DRAM, 2 HDD (40 GB for children's Win98, and 8 GB for
> NetBSD).
>
> I do not understand the memory output in TOP application. How to read
> it? The problem I have concerns slowness of the system running NetBSD
> with Deer Park. I did not have the problems working with Debian.
>
> Deer Park seams to take up part of swap partition than chunk of memory
> what makes every page opens too slowly. God forbid if I run ogg
> encoder then. Which is a must for me as I have to record some radio
> talk shows.
>
> There's "Inact" field in TOP readout, what I read as
> "inactive". Sometimes both Inact and swap Used size are equal. If I
> was able to use the Inact memory I wouldn't use swap and Deer Park
> responsivness would be improved. Am I right? I badly need the free
> memory. I suppose I'm right as some small scripts run very fast, what
> in Debian would be impossible due to swap-memory exchanges.
> 
> Is there any way to deal with memory usage in NetBSD?
> 
> I recorded four TOP outputs.
> 
> 1) System has just started without any applications (with X)
> load averages:  0.79,  0.36,  0.15                                                         05:37:52
> 32 processes:  1 runnable, 30 sleeping, 1 on processor
> CPU states:  1.0% user,  0.0% nice,  2.0% system,  0.0% interrupt, 97.0% idle
> Memory: 44M Act, 500K Wired, 13M Exec, 13M File, 56M Free
> Swap: 300M Total, 300M Free
> 
> 2) Deer Park running
> load averages:  1.03,  0.49,  0.20                                                         05:38:46
> 33 processes:  32 sleeping, 1 on processor
> CPU states: 52.2% user,  0.0% nice,  2.0% system,  0.0% interrupt, 45.8% idle
> Memory: 92M Act, 668K Wired, 31M Exec, 22M File, 7904K Free
> Swap: 300M Total, 300M Free
> 
> 3) After some time
> load averages:  1.24,  1.15,  1.02                                                         06:30:49
> 38 processes:  1 runnable, 36 sleeping, 1 on processor
> CPU states: 55.2% user,  0.0% nice, 10.0% system,  0.0% interrupt, 34.8% idle
> Memory: 69M Act, 35M Inact, 624K Wired, 26M Exec, 9520K File, 1160K Free
> Swap: 300M Total, 19M Used, 281M Free
> 
> 4) More time passed...
> load averages:  1.23,  1.16,  0.88                                                         07:42:06
> 32 processes:  1 runnable, 30 sleeping, 1 on processor
> CPU states:  0.0% user,  0.0% nice,  0.0% system,  0.5% interrupt, 99.5% idle
> Memory: 41M Act, 20M Inact, 536K Wired, 9344K Exec, 43M File, 44M Free
> Swap: 300M Total, 23M Used, 277M Free

Doesn't look like it's a memory issue.  All your CPU time is being used
in user-space, not system, which would suggest NetBSD is just spending
a lot of time executing the program, not spending a lot of time paging
stuff on and off disk.

I'd watch the output of 'vmstat 5' for a while before and during use of
this program to verify.

Is Deer Park compiled natively for NetBSD?  Or are you running the Linux
version under emulation?

-- 
Michael Parson
mparson@bl.org