Scheduler fixes for hyperthreading
marcel at xcllnt.net
Sat May 21 18:04:22 PDT 2005
On May 21, 2005, at 5:49 PM, Colin Percival wrote:
> Marcel Moolenaar wrote:
>> On May 21, 2005, at 4:11 PM, Colin Percival wrote:
>>> The following must be done before hyperthreading is re-enabled:
>> Maybe it's a better idea to describe the problem in much more
>> detail, rather than dictate what you want someone else to do?
>> A pointer to where the problem is described/discussed would
> The problem is described in my paper "Cache missing for fun and
> Put simply, threads which share a processor core can monitor each
> memory access patterns, so we need to ensure that such co-scheduling
> happens between threads which have different privileges.
I'll be studying your paper to see if it can be shown that the HT
implementation in Itanium is affected as well. If not, any solution
must be sufficiently machine dependent.
> The reason I cut through to explaining what needed to be done is that
> I discussed this at length with several people from the FreeBSD
> team before and during BSDCan; but these discussions were obviously not
> public, so I can't give a reference to them.
I can only assume that the discussion was i386 centric (as this is
typically the case). Hence my request for a problem description.
Marcel Moolenaar USPA: A-39004 marcel at xcllnt.net
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