[ut2004] ut2004 on linux PPC?

Ryan C. Gordon icculus at clutteredmind.org
Fri Apr 23 13:03:41 EDT 2004


> I'd much rather see an AMD64 dedicated server before a PPC64 dedicated 
> server, but both would be cool.  PPC64 doesn't offer any instrinic 

There's already an amd64 server. Ships in the retail box, and it's
included in the server-only download.

> performance increase over PPC32--it'll probably be slightly slower due 
> to increased address sizes.  However, the 64-bit x86 extension should 
> give a 15-30% boost in performance by fixing problems in the ISA that 
> PPC never had (ie it abandons the floating point stack and other legacy 
> stuff completely, and it doubles the number of usable registers). 

The floating point stack isn't disabled in longword mode on the amd64.
However, Win64 doesn't save the floating point stack's state on context
switch, so you can't use them reliably and the compiler doesn't generate
code for it anyhow. Still, the registers are still accessible (but
useless, since they could change at any time from under you) if you
write assembly code. That being said, Microsoft's amd64 Platform SDK
doesn't let you write inline assembly, so you basically have no
reasonable access to the legacy FPU even if you wanted it.

amd64 linux saves the FPU on context switch, and the compiler generates
code for it...probably because it was easier to bootstrap GCC from the
x86 target. Microsoft's platform SDK doesn't use the FPU at all...all
floating point is done through SSE...SSE is smokin' fast on AMD's chips
compared to the FPU, so this was an interesting decision on Microsoft's
part.

> An AMD64 server is important because that 15-30% boost in performance 
> (it's 30% for the halflife engine anyway) equates to an equal decrease 

Don't believe everything that you read.  :)

> So, an AMD64 dedicated server should allow some current AMD processors 
> and future Intel processors to give more clients a better experience.  
> By better, I mean more emmersive, more interactive, less delay.

I think that the real gains will be client-side, honestly. Dedicated
servers generally don't use all the existing CPU resources in this day
and age.

--ryan.






More information about the ut2004 mailing list