2.6.14.5 / swapping / killing random apps

2.6.14.5 / swapping / killing random apps

[Trilight]

Hiya all,

I was wondering about the following;


kernel: 2.6.14.5 / vanilla

If a system with say a swap of 2GB on a fast drive and like 260MB is
actively used for swapping, could it cause certain applications to crash
? I noticed that the when swapping occurs, usualy above 200MB then
random apps start to crash. Sometimes gnome-terminal, gnome-panel,
xchat, metacity and so on. It happens a few times in usually 48 hours.

The system has 512MB ram, ECC , checked and cleared. The system can be
booted with m$ xp or freebsd but crashes do not occur even under heavy
load. So that's why i'm thinking something is causing this behaviour in
linux. I also have to say that dmcrypt was used for the swap but that
caused the crashes to increase, so dmcrypt is not used anymore just a
normal swap and crashes decreased to "rare" within 24 hours.

Or is it "normal" that the crash risk of running apps increases the more
swapping is done ?

I plan to upgrade the memory to 1.5GB anyway, but this issue is kinda
bothering me.

Thanks in advance for any input !

Mark

Re: 2.6.14.5 / swapping / killing random apps

[Jesper Juhl]

On 12/29/05, Trilight <trilight@ns666.com> wrote:
> Hiya all,
>
> I was wondering about the following;
>
>
> kernel: 2.6.14.5 / vanilla
>
> If a system with say a swap of 2GB on a fast drive and like 260MB is
> actively used for swapping, could it cause certain applications to crash
> ?

It shouldn't.


>I noticed that the when swapping occurs, usualy above 200MB then
> random apps start to crash. Sometimes gnome-terminal, gnome-panel,
> xchat, metacity and so on. It happens a few times in usually 48 hours.
>
> The system has 512MB ram, ECC , checked and cleared. The system can be
> booted with m$ xp or freebsd but crashes do not occur even under heavy
> load. So that's why i'm thinking something is causing this behaviour in
> linux. I also have to say that dmcrypt was used for the swap but that
> caused the crashes to increase, so dmcrypt is not used anymore just a
> normal swap and crashes decreased to "rare" within 24 hours.
>

> Or is it "normal" that the crash risk of running apps increases the more
> swapping is done ?
>
No.  Not unless you exhaust *all* you RAM+Swap - if the machine goes
OOM then the OOM-Killer will kick in and kill one or more applications
in order to keep the system alive, but from your description (only
260MB Swap used out of 2GB) that does not seem to be the case here.


> I plan to upgrade the memory to 1.5GB anyway, but this issue is kinda
> bothering me.
>
> Thanks in advance for any input !
>

Only thing I can think of would be a corrupted swap
partition/swap-file or bad blocks on the harddrive in the areas used
to hold the swap. That could be one possible explanation and would
also explain that other OS's on your box doesn't crash since they
don't use the same parts of the disk for swap.

Maybe someone else has other possible explanations.


--
Jesper Juhl <jesper.juhl@gmail.com>
Don't top-post  http://www.catb.org/~esr/jargon/html/T/top-post.html
Plain text mails only, please      http://www.expita.com/nomime.html

Re: 2.6.14.5 / swapping / killing random apps

[Trilight]

Jesper Juhl wrote:
> On 12/29/05, Trilight <trilight@ns666.com> wrote:
> 
>>Hiya all,
>>
>>I was wondering about the following;
>>
>>
>>kernel: 2.6.14.5 / vanilla
>>
>>If a system with say a swap of 2GB on a fast drive and like 260MB is
>>actively used for swapping, could it cause certain applications to crash
>>?
> 
> 
> It shouldn't.
> 
> 
> 
>>I noticed that the when swapping occurs, usualy above 200MB then
>>random apps start to crash. Sometimes gnome-terminal, gnome-panel,
>>xchat, metacity and so on. It happens a few times in usually 48 hours.
>>
>>The system has 512MB ram, ECC , checked and cleared. The system can be
>>booted with m$ xp or freebsd but crashes do not occur even under heavy
>>load. So that's why i'm thinking something is causing this behaviour in
>>linux. I also have to say that dmcrypt was used for the swap but that
>>caused the crashes to increase, so dmcrypt is not used anymore just a
>>normal swap and crashes decreased to "rare" within 24 hours.
>>
> 
> 
>>Or is it "normal" that the crash risk of running apps increases the more
>>swapping is done ?
>>
> 
> No.  Not unless you exhaust *all* you RAM+Swap - if the machine goes
> OOM then the OOM-Killer will kick in and kill one or more applications
> in order to keep the system alive, but from your description (only
> 260MB Swap used out of 2GB) that does not seem to be the case here.
> 
> 
> 
>>I plan to upgrade the memory to 1.5GB anyway, but this issue is kinda
>>bothering me.
>>
>>Thanks in advance for any input !
>>
> 
> 
> Only thing I can think of would be a corrupted swap
> partition/swap-file or bad blocks on the harddrive in the areas used
> to hold the swap. That could be one possible explanation and would
> also explain that other OS's on your box doesn't crash since they
> don't use the same parts of the disk for swap.
> 
> Maybe someone else has other possible explanations.
> 
> 
> --
> Jesper Juhl <jesper.juhl@gmail.com>
> Don't top-post  http://www.catb.org/~esr/jargon/html/T/top-post.html
> Plain text mails only, please      http://www.expita.com/nomime.html
> -
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
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> 
> 


Thanks for your reply !

I just did bad block check and it turns out to be good.

If there is anything else i can check i'm all ears hehe

Re: 2.6.14.5 / swapping / killing random apps

[Jesper Juhl]

On 12/29/05, Trilight <trilight@ns666.com> wrote:
<!-- snip -->
>
> I just did bad block check and it turns out to be good.
>
> If there is anything else i can check i'm all ears hehe
>
Have you checked you log files/dmesg for clues after an occourance of
the problem?
Have you checked the logs for interresting messages leading up to the problem?

--
Jesper Juhl <jesper.juhl@gmail.com>
Don't top-post  http://www.catb.org/~esr/jargon/html/T/top-post.html
Plain text mails only, please      http://www.expita.com/nomime.html

Re: 2.6.14.5 / swapping / killing random apps

[Trilight]

Jesper Juhl wrote:
> On 12/29/05, Trilight <trilight@ns666.com> wrote:
> <!-- snip -->
> 
>>I just did bad block check and it turns out to be good.
>>
>>If there is anything else i can check i'm all ears hehe
>>
> 
> Have you checked you log files/dmesg for clues after an occourance of
> the problem?
> Have you checked the logs for interresting messages leading up to the problem?
> 
> --
> Jesper Juhl <jesper.juhl@gmail.com>
> Don't top-post  http://www.catb.org/~esr/jargon/html/T/top-post.html
> Plain text mails only, please      http://www.expita.com/nomime.html
> 
> 




I did, but there is no sign in the logs indicating something about the
app which crashed at that moment.