[ardour-users] [OT] AMD Bugs

[Paul Davis]

On Tue, 2005-12-20 at 14:21 +0100, Mario Torre wrote:
> Hi!
> 
> Forgive me for this OT... Well this is not too much OT, really a bit... :)
> 
> Some time ago I have read an interesting thread on this list about 64 
> bit systems. Someone said that the AMD 64 dual core had a design bug 
> that lead to poor performance in certain situations.
> 
> I would like to know more about that (I could not find anything on 
> google!), and to know if the Opteron 848 is affected by this bug, as we 
> are about to build few workstations based on these processors.

the problem is that the TSC (cycle counter) is not synced on these
systems, so software which uses the cycle counter to provide lightweight
(single instruction) high resolution timing in user space can get a
garbled (and possibly fatal) idea of the current time. its caused by CPU
speed adjustments due to power management.

there are fixes for JACK floating around and destined to appear in CVS
soon that will avoid the problem. go ahead and buy the system you want.

--p