Upgrading from 32bit to 64 bit OS on 2950

[McDougall, Marshall (FSH)]

>-----Original Message-----
>From: linux-poweredge-bounces at dell.com 
>[mailto:linux-poweredge-bounces at dell.com] On Behalf Of Brendan Heading
>Sent: Thursday, May 03, 2007 10:19 AM
>To: linux-poweredge at dell.com
>Subject: Re: Upgrading from 32bit to 64 bit OS on 2950
>
>McDougall, Marshall (FSH) writes: 
>
>> On my first foray into the 2950 I installed the 32bit 
>RHEL4U4.  I have
>> been told of the error in my ways and now I want to install 
>the 64 bit
>> version.  I have never done the 64 bit install and am 
>wondering if I can
>> simply do an upgrade or do I need to start from scratch?  Any advice
>> appreciated, and yes I will RTFM as well.  Thanks.
>
>You must reinstall from scratch. 
>
>NB who told you that 32bit was an "error" ? There are many 
>cases where 64bit 
>systems do not perform measurably better. I would always 
>install the 32 bit 
>version unless there was a specific, well established reason 
>to go 64 bit. 
>
>Brendan 
>
>_______________________________________________
>Linux-PowerEdge mailing list
>Linux-PowerEdge at dell.com
>http://lists.us.dell.com/mailman/listinfo/linux-poweredge
>Please read the FAQ at http://lists.us.dell.com/faq
>
Thanks for the reply, Brendan.

This all precipitated when we started migrating our Sybase ASE 12x off
of 2650's running ES3 and putting them on 2950's with ES4.  We went
from:
2650 with 2x3.2GHz cpu, 4GB ram, 5x146GB U320 in RAID5 and ES3   
 to
2950 with 2x3GHz Xeon 5160's, 8GB ram, 6x146GB SAS drives in RAID 10 and
ES4.

Our performance benchmarks show a significant slowdown on the 2950's
compared to 2550's on Sybase inserts, updates, and deletes.

ES3 included librtkaio libraries for kernel io and Sybase utilized those
libraries heavily.  Those libs are not present in ES4.  When I asked RH
about it, one of their suggestions was to install the 64 bit version of
ES4.

Regards, Marshall