High Utilization kswapd and kupdated in Large memory system

High Utilization kswapd and kupdated in Large memory system

[vwake]

Hi,
On large memory machine ( 32 GB RAM) any continuous disk activity puts kswapd and kupdated to 99% utilization and eventually ( in about 10 mins) brings down the whole machine.

The machine works well when the memory was set at 4GB using the 'mem=" entry on grub.conf. The same disk operations succeed when kept in this config.


The kernel is version 2.4.22 stable downloaded from kernel.org, and compiled with 64GB option enabled. The machine is installed with Redhat Linux 9.0.

No errors gets logged anywhere and also there are no console error messages. The machine eventually gets locked up, and only a hard reset will bring it back into shape. I do not suspect the hardware because it is reproduceable in a different machine with similar hardware config.

The hardware config as below:

Dell PE 6650 / 4* Xeon 2GHz / 32 GB RAM / 500 GB Raid 5 on PERC 3DC ( AMI megaraid driver) 6 DISCS / 2* Broadcom 100/1000 NIC ( bcm5700 driver) 

The system has / and /boot in ext3 and rest in ReiserFS. The 500 GB data partition is in ReiserFS.

The problem is reproducible by just copying some large data ( 3-5 GB ) to any of the filesystems.
One observation ( may not be useful) is that the symptoms starts after the cached memory in /proc/meminfo goes beyond 16GB !


I had tried changing the "elvtune" parameters to " -r 4096 -w 8192" as adviced in some of the archived maillist mails. But this didnt help !

Please let me know if any further information is needed from the machine.

Thanks... 

Vivek



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Re: High Utilization kswapd and kupdated in Large memory system

[Andrew Morton]

"vwake" <vwake@indiatimes.com> wrote:
>
> On large memory machine ( 32 GB RAM) 
> ...
> The kernel is version 2.4.22

Not a chance, my friend.

Try 2.4.23-pre8, or 2.6.

Re: High Utilization kswapd and kupdated in Large memory system

[Marcelo Tosatti]

On Thu, 23 Oct 2003, vwake wrote:

> Hi,
> On large memory machine ( 32 GB RAM) any continuous disk activity puts kswapd and kupdated to 99% utilization and eventually ( in about 10 mins) brings down the whole machine.
> 
> The machine works well when the memory was set at 4GB using the 'mem="
> entry on grub.conf. The same disk operations succeed when kept in this
> config.
> 
> 
> The kernel is version 2.4.22 stable downloaded from kernel.org, and compiled with 64GB option enabled. The machine is installed with Redhat Linux 9.0.
> 
> No errors gets logged anywhere and also there are no console error
> messages. The machine eventually gets locked up, and only a hard reset
> will bring it back into shape. I do not suspect the hardware because it
> is reproduceable in a different machine with similar hardware config.
>
> 
> The hardware config as below:
> 
> Dell PE 6650 / 4* Xeon 2GHz / 32 GB RAM / 500 GB Raid 5 on PERC 3DC ( AMI megaraid driver) 6 DISCS / 2* Broadcom 100/1000 NIC ( bcm5700 driver) 
> 
> The system has / and /boot in ext3 and rest in ReiserFS. The 500 GB data partition is in ReiserFS.
> 
> The problem is reproducible by just copying some large data ( 3-5 GB ) to any of the filesystems.
> One observation ( may not be useful) is that the symptoms starts after the cached memory in /proc/meminfo goes beyond 16GB !
> 
> 
> I had tried changing the "elvtune" parameters to " -r 4096 -w 8192" as adviced in some of the archived maillist mails. But this didnt help !
> 
> Please let me know if any further information is needed from the machine.

Hi, 

Can you please try 2.4.23-pre?

There have been significant highmem balancing changes.