[chandler-users] Performance: Chandler desktop 1.0.3 RC1 on Mac OS X 10.5.6, Intel and PowerPC, profile on USB flash drive

Rob Stearn robstearn at me.com
Mon Feb 23 02:02:14 PST 2009

I think this might be completely the wrong way round....

The Xeon processor will of course be faster than the Core Duo, it's  
after all a workstation class chip.
This seems at odds also with the PPC/Intel comparison made in the  
previous line as they are both Intel archs.

The PPC architecture used in Macs was limited to a system bus speed  
of, at the most, 166mhz.
Even though the RAM in later PPC machines was DDR/DDR2 (Meaning Double  
Data Rate) the systems were only really using at Single Data Rate  

The exception to this rule was the G5 which was based more fully on  
IBMs POWER line of processors and had much greater memory and system  
bus speeds, though  the numbers escape me.

The greatest advantage of Intel for the Mac has been the ability to  
rapidly increase the system bus speeds up to those of there PC  
counterparts, the most recent portables have a 1066mhz bus which is  
almost 10x faster than the last-in-line G4 desktops.

Just to clarify...

So if you're observing greatly increased speeds in PPC than in Intel,  
it isn't memory bandwidth thats causing it.
 From a troubleshooting POV, I would suspect:

Disk defragmentation (yes it can happen on Macs too)
Remaining Disk space
An indication a fresh install is needed, multiple upgrades  
10.3>10.4>10.5 especially bridging architectures leaves a lot of stuff  
you don't need.
Something very wrong in the quality of the Python distro thats provided
Another process taking up CPU.
All or some of the above.

 From my experience PPC machines running Chandler are accompanied with  
the soft whistle of fans.

On 23 Feb 2009, at 08:30, Graham Perrin wrote:

> William K. Volkman wrote:
>> Last time I really analyzed these systems (2002) the PPC had about  
>> 8X the
>> memory bandwidth capability of the Intel architecture. So I would  
>> expect a
>> memory intensive application to run about 8X faster on that older
>> architecture. … If you compare the memory performance of your circa  
>> 2002
>> 2.0Ghz Intel Xeon processor you'll find it about 4X faster than the  
>> shiny
>> new Core Duo you just bought. Marketing works.
>> HTH,
>> William.

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