This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
Home Products Support Community News


[Xen-devel] Re: HPET/PIT timer accuracy

On 29 Jul 2005, at 18:53, Ian Pratt wrote:

Any ideas what could be going on?! This is something of a
pain for the new time code, which syncs the local TSCs to the
chipset timer....

These systems haven't got a 'spread spectrum'[*] PCI bus clock per
chance? It might be worth seeing if there's a BIOS option for it.

I did check one of our machines, and spread spectrum was definitely disabled. In any case, I'd expect that to jitter the clock at some high frequency, but not add/remove ticks in a way that would be discernable at 1Hz.

 -- Keir

Xen-devel mailing list

<Prev in Thread] Current Thread [Next in Thread>