How to decrease the used memory in KDE 4.7.2?

[realfer]

After login to KDE 4.7.2 in openSUSE 12.1 I was surprised that over 1.1 GB is used with no user applications ran. In 11.4 it was 2 times less. What is the typical amount of memory used just after login with no user applications ran? How can I decrease this amount? I have dozens of akonadi_agent_launcher threads.

[DenverD]

On 01/17/2012 02:36 PM, realfer wrote:
>
> After login to KDE 4.7.2 in openSUSE 12.1 I was surprised that over 1.1
> GB is used with no user applications ran. In 11.4 it was 2 times less.
> What is the typical amount of memory used just after login with no user
> applications ran? How can I decrease this amount?

why do you want to decrease it....it will just full up anyway...that is
the Linux way (versus the Windows way of emptying every chance it gets.
read more:
<http://forums.opensuse.org/english/get-technical-help-here/install-boot-login/471141-invalid-opcode.html#post2430261>


> I have dozens of akonadi_agent_launcher threads.

if you are not using any of KDE's PIM apps and want to disable that, see
here: http://ubuntuku.org/16/how-to-disable-nepomuk-akonadi/

it worked for me.

--
DD http://tinyurl.com/DD-Caveat http://tinyurl.com/DD-Hardware
http://tinyurl.com/DD-Software
openSUSE®, the "German Engineered Automobiles" of operating systems!

[realfer]

why do you want to decrease it....it will just full up anyway...that is
the Linux way (versus the Windows way of emptying every chance it gets.

Maybe I expressed my thoughts not that clear. I will try again. The previous KDE needed significantly less memory, than KDE 4.7. Two times is much, isn't it? I don't mean cache etc. I mean that when I had 4 GB on 11.4 I could use ~3.5 GB for user applications. Now I can use < 3 GB. This is sad, because I didn't get something very-very useful instead of those 500 or 600 MB.
Sure, I could use XFCE, but earlier 0.5 GB was quite enough for KDE 4, it was not that "monster-like" DE.

[DenverD]

you are not understanding how linux uses RAM..
you have 4GB for use...and you will use it all, because that is the way
linux does it...

--
DD
openSUSE®, the "German Engineered Automobiles" of operating systems!

[robin_listas]

On 2012-01-17 15:52, DenverD wrote:
> you are not understanding how linux uses RAM..
> you have 4GB for use...and you will use it all, because that is the way
> linux does it...

That is true, but you can compare the amount used (by processes). If at
start you see an amount with one version of the system and now another,
bigger amount, I would think first that there are now more processes
running. If it is the same processes, then the current version has
differences in those processes. What are the differences, I dunno.

--
Cheers / Saludos,

Carlos E. R.
(from 11.4 x86_64 "Celadon" at Telcontar)

[realfer]

you are not understanding how linux uses RAM..
you have 4GB for use...and you will use it all, because that is the way
linux does it...

No, I understand common principles.
Let me illustrate what you said and what I meant exactly. I will show 4 screenshots of KSysGuard. Let's compare them.

1.This is what I see when I login Fedora 16 with KDE. I see 0.37 MB total used memory just after KDE login. I think this is quite a reasonable amount of memory for KDE. This screenshot was made on another laptop with Fedora, but no matter. By the way, there are no akonadi_agent_launcher threads.

What I see when I login to KDE in openSUSE 12.1? I will use detailed plots in KSysGuard to explain what I meant in previous posts.

2. Just after login I see something like this . There is over 1.1 GB used by KDE's applications and about 300 MB are cached. I had not launched nothing but KSysGuard and KSnapShot by that moment. The difference between Figure 1 and Figure 2 is clear. In the first case we have 800 MB more RAM available for applications than in the second one (if we had equal memory amounts on both laptops, sure).

The cached memory grows during the work. And here you are right, saying about differences between Windows and Linux. Almost all available memory is used by applications, cache and buffer memory. Last two can be released for application needs. I don't say now about swappiness. What I want to say is that memory used is not the same as memory cached or buffered. Good words are here and here:

Cached Memory and Buffered Memory are dynamic pools used to decrease the number of disk accesses that must be done. In a healthy system, most of the physical memory is used up by the total of these three items because that is more efficient. The real indication that more RAM would be beneficial for your system is when most of the physical memory is being used as application memory.

Now is what I have on my openSUSE 12.1 laptop in detail.

3. When I work the RAM is preferably used by applications (~2.2 GB).

4. I launched VirtualBox which uses more than 1 GB for the OS installed there. The memory needed for VirtualBox is partially taken by clearing cached data, exactly what you said.

Conclusion. KDE in openSUSE 12.1 uses much more memory than it uses in Fedora (and - you can trust me - in openSUSE 11.4). At least here, on my laptop. In other words, the question in the first post of the thread was: "What is the typical amount of memory used after login at an average computer? How to make available more memory for applications?" And, although I cannot show you KDE memory usage in openSUSE 11.4, you can trust me, it used significantly less memory.

I am sorry for some Russian in figures. All important things are in English.

[realfer]

Well... I have found an answer. Maybe someone else will use this experience.
A lot of memory was used by akonadi_agent_launcher processes. There were 88 weird personal data sources in Akonadi settings. I removed them all because I don't use Akonadi. As a result I have released more than 500 MB and I am satisfied. The only question - where did those personal data sources come from? I didn't use KMail, etc.

[DenverD]

On 01/18/2012 12:36 AM, realfer wrote:
>
> Well... I have found an answer. Maybe someone else will use this
> experience.
> A lot of memory was used by akonadi_agent_launcher processes. There
> were 88 weird personal data sources in Akonadi settings. I removed them
> all because I don't use Akonadi.

i told you how to do that in my first post..


> As a result I have released more than
> 500 MB and I am satisfied. The only question - where did those personal
> data sources come from? I didn't use KMail, etc.

i have never used KMail or the PIM stuff in KDE either..

but, in a default install of 11.4 with KDE i had wild Akonadi workers
doing something...and, killed them once i learned what it was about..

where did they come from? they came from the "default install" of KDE4.x
on openSUSE (but, i don't know which version of openSUSE they first
appeared on)..

so, when you compare one distribution to another it is very important to
do your best to not compare "apples to oranges"...that is, if you had
added the Akonadi overhead to Fedora i bet you would have seen similar
RAM usage there..

i suppose you might want to know why a default install of openSUSE 11.4
& 12.1 includes Akonadi and Fedora 16 does not--and, i'd say it is just
one more (of hundreds or thousands?) of packaging decisions made by the
different developer communities...and, we can both be happy we know how
to avoid the Akonadi plague, and have the absolute freedom to leave one
distro for another...

one last thing: i know you understand the basic differences in
windows/linux memory usage, yet still i think you miss one interesting
point:

you looked at the initial use of RAM and wrote "In the first case we
have 800 MB more RAM available for applications than in the second one"

your statement is a true fact, but only at _that_ instant in time...

what it seems to me you don't yet fully understand is that as (for
example) the Akonadi workers complete their tasks and fall idle (or
exit), practically *all* of the RAM they had tied up _initially_ is
available for use by those other applications you wanted that 800 MB
available to..

let me suggest you to open a konsole/terminal/xterm and start up top,
where you will see an always changing view of the amount of "MEM"
(memory, actually RAM) each process in the list is _using_ as the
seconds tick by..

if you adjust the window to see as much of the list as possible you will
notice the list of processes is long! (too long to see them all on my
monitor)...and, you will notice that those processes are arranged by
cpu/memory usage, with those using the most system resources at the top
of the list....and, as you go down the list _very_ soon you see row
after row of processes using zero percent of both CPU and RAM...which
means that if suddenly you open a flash video (or do a huge database
search--or *anything*) all of the RAM not actually being used (by all of
those zero cpu, zero ram processes) will near instantly be available for
your movie pleasure...

because Linux dynamically assigns RAM _as needed_ among the processes
running/idle..

that is _not_ the case in Windows....in Windows RAM used is *used* and
not available to anything except the application/program/process which
grabbed it..

and that is why there is so much concern in the Windows World about
_initial_ RAM use (because that RAM is _not_ usable by any application,
at any time...until the app is closed and Windows does the tidy up)..

but, in Linux is not that big a deal because the kernel does a pretty
good job of making memory available where needed....and, the system
administrator can use 'nice' to assign priorities among the various
processes..

make sense?

--
DD http://tinyurl.com/DD-Caveat http://tinyurl.com/DD-Hardware
http://tinyurl.com/DD-Software
openSUSE®, the "German Engineered Automobiles" of operating systems!

[realfer]

Thank you for your comprehensive answer. I understand your analogy with "apples" and "oranges" and I mentioned above that those are two different distributions. By the way, there IS akonadi in Fedora. My problem was solved by cleaning user data sources.
But I have got a question about the memory. I don't use the swap. When my memory goes 100% used by applications and cache/buffer memories are 0, will my system freeze? Because of the absence of the memory.

[robin_listas]

On 2012-01-18 12:46, realfer wrote:
> When
> my memory goes 100% used by applications and cache/buffer memories are
> 0, will my system freeze? Because of the absence of the memory.

The kernel will start killing apps to survive - and not always succeeding.

--
Cheers / Saludos,

Carlos E. R.
(from 11.4 x86_64 "Celadon" at Telcontar)