SQL Server Performance Forum – Threads Archive

Hyper-threading with 1 cpu with dual core

We have an IBM e-server with 1 CPU with dual core. The cpu speed is 2.8 Ghz. When hyper-threading is on, I see four CPU’s in the task manager. In Bios under the system summary, it shows both CPU’s ID and CPU’s speed are same. When I turn off the hyper-threading, the task manager only shows one CPU. When I go to the bios, one of the CPU ID and its speed become zero. Is it supposed to be that way? Actually I was expecting to see two CPU’s in task manager when I turned off hyper-threading since it shows four when it is on. Second question is that will SQL 2K5 utilize hyper-threading much better than SQL 2K that I should leave hyper-threading on no matter what. Any clarification on this matter is very much appreciated. Wingman

---

hyper-threading is still problematic
you might consider setting affinity limiting SQL to the lower 2 procs

---

Thank for the quick response. can you answer my first question also, "Is is supposed to show only 1 CPU in task manager if hyper-threading is turned off?" Again it is a 1 CPU with dual core system. wingman

---

]]>