I am just wondering if it is normal. I have two xeon processors with HT on each of them. When loading kernel says that 4 cpu's are found, but when i do top i can see only 0 or 2 in the C column. never 1 or 3. Is it normal? FreeBSD 6.2-STABLE (cvsed 1 day ago) -- Regards. Artem
Artem Kuchin wrote:> I am just wondering if it is normal. > I have two xeon processors with HT on each of them. > When loading kernel says that 4 cpu's are found, > but when i do top i can see only 0 or 2 in the C > column. never 1 or 3. Is it normal? > > FreeBSD 6.2-STABLE (cvsed 1 day ago)If I remember correctly, HT is disabled by default for security reasons but there should be a sysctl to enable it. I believe there is also a paper by Colin Percival on the issue. Note that in a lot of common loads, the use of HT with the standard scheduler does not yield any real benefits. Regards, Richard
On Wed, 25 Apr 2007 15:26:02 +0400, "Artem Kuchin" <matrix@itlegion.ru> wrote:> I am just wondering if it is normal. > I have two xeon processors with HT on each of them. > When loading kernel says that 4 cpu's are found, > but when i do top i can see only 0 or 2 in the C > column. never 1 or 3. Is it normal?Hyperthreading has been disabled by default for quite some time now. More info (including ways to reenable HTT) can be found here: http://security.freebsd.org/advisories/FreeBSD-SA-05:09.htt.asc Regards, S?ren Klintrup