Hi. I just got a new HT system, so I installed kernel-smp-2.4.22-1.2174.nptl onto my Fedora hard disk and plugged it in. The dual CPUs are detected, and reading /proc/interrupts shows that interrupts are indeed being balanced between the two, but application code is only being run on CPU0, never on CPU1!!! I have tried running a bunch of all-cpu, no-io processes, but no good...always CPU 0 gets 100% load, but CPU1 sits there at 0% (unless there are a lot of interrupts, then it's system time might creep up to 0.1%). Some other strange things are happening (some of these will be comparisons with my other HT systems, which run RHEL3, and properly use both logical CPUs): * "top" on an unloaded system shows "idle" to be the sum of CPU0 and CPU1, not the average. Since cpu1 is always 100% idle, that means that the "total" line is always in the 100%..200% area. * The "migrate/0" and "migrate/1" kernel threads do not appear in "ps aux". On the RHEL3 systems, these threads appear; does the FC1 kernel require these threads? If so, why wouldn't they be started? * "x86info" shows "Number of logical processors supported within the physical package: 0" for the FC1 system. On the RHEL3 system, it properly shows "2" instead. I'd like to try plugging the RHEL3 disks into the FC1 system to see if it is a hardware issue, but they are at a remote site so that isn't possible. Anybody know what this could be? More info in case it helps: $ uname -r 2.4.22-1.2174.nptlsmp $ cat /proc/cpuinfo processor : 0 vendor_id : GenuineIntel cpu family : 15 model : 2 model name : Intel(R) Pentium(R) 4 CPU 2.80GHz stepping : 9 ... etc ... processor : 1 vendor_id : GenuineIntel cpu family : 15 model : 2 model name : Intel(R) Pentium(R) 4 CPU 2.80GHz stepping : 9 ... etc ... $ BIOS says HT is enabled. Those model/stepping parameters are exactly the same as seen on the RHEL3 systems which work fine. Please let me know what could be causing this, I'd like to get to actually use the HT for more than IRQ balancing! Bill Shubert (wms@xxxxxxxxxx)
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