[lug] server memory woes (3rd attempt!)

Michael Belanger mrb at ciclops.org
Fri Aug 27 08:24:32 MDT 2004

Nate Duehr wrote:

> One comment here... common mistake on large RAM boxes...
> 6GB of swap will pretty much be useless to you and is wasted space.  If 
> you calculate how long it would take to swap 6GB of data in and out 
> under the kind of load that would require that level of swapping, you'll 
> see that the box will likely die or become completely unresponsive long 
> before you can ever "get there".

What is funny is that I knew this from being told a couple years ago --- 
but out of habit, I still doubled the RAM for swap.. DOH!

> What kind of box is it?  Most "fell off the network and console won't 
> respond locally" types of lockups I've seen over the years are the 
> result of either a piece of hardware acting flakey (usually a bad RAM 
> SIMM/DIMM) or a bug in the kernel drivers for a particular piece of 
> on-board hardware, usually NIC's that don't play nicely.  Have also seen 
> a few broken DMA implementations that would manifest themselves in 
> wicked lockups with nasty data corruption, but that's super-rare and 
> many years ago.

It is a Western Scientific :

  Server Model: WS-2UOPT/3GB (Fusion A64 )
motherboard: Arima HDAMA, Dual 100/1000, 8x Memory Slots
CPU: (2) Opteron 240, 1.4Ghz
System Disk: 80GB 7200 RPM IDE
RAID: 8 @ 200GB 7200 RPM SATA Drives
Memory: 3GB Registered ECC DDR 333, PC2700, 6x 512MB
3-Ware 8506-8, 8-port SATA RAID Card

The 3-Ware card model number was not listed on the RH suppported 
hardware list, but another model similar was.

> When the machine stops responding on the network, is the local console 
> still alive?

The console is locked up when it stops responding.

> -- 
> Nate Duehr, nate at natetech.com
> _______________________________________________
> Web Page:  http://lug.boulder.co.us
> Mailing List: http://lists.lug.boulder.co.us/mailman/listinfo/lug
> Join us on IRC: lug.boulder.co.us port=6667 channel=#colug

Michael Belanger
CICLOPS, Space Science Institute

phone. 720-974-5853   Jabber: mrb at jabber.ciclops.org
fax.   720-974-5860

The Sender and Cassini Imaging Central Laboratory for Operations
accepts no liability for the content of this email, or for the
consequences of any actions taken on the basis of the information
provided, unless that information is subsequently confirmed in
writing. If you are not the intended recipient you are notified
that disclosing, copying, distributing or taking any action in
reliance on the contents of this information is strictly prohibited.

More information about the LUG mailing list