newbie SMP questions

Petri Helenius pete at
Mon Jan 19 11:38:54 PST 2004

Chris Stenton wrote:

>I've just built a dual XEON box running 5.2. Could someone give me some
>pointers on the following.
>1. I can't find a thread on the pro and cons of having HTT enabled.
>The issue must have been flogged to death somewhere.
If you run things that spend considerable time behind Giant, disable HTT.
There is also an issue with at least HTT where the system panics on boot
asking "AP #n failed panic y/n?".
For general application/server use, you probably benefit from HTT.

 >2. An old rule of thumb for a single processor machine was to have twice

>the amount of swap space to physical RAM. Is this still the case for a 4
>logical CPU machine? I never understood where that rule of thumb came
Does >4G swap work alright anyway?


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