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1.25.  cpuspeed

1.25.1.  RHBA-2009:0424: bug fix update


This update has already been released (prior to the GA of this release) as FASTRACK errata RHBA-2009:0424
An updated cpuspeed package that fixes various bugs is now available.
The cpuspeed package provides CPU frequency scaling support.
This updated package fixes the following bugs:
  • the cpuspeed init script loaded the speedstep-centrino driver on Intel systems, even when the acpi-cpufreq driver had already loaded successfully. With both these drivers loaded, the system would not handle P-states correctly. The cpuspeed init script now attempts to load the speedstep-centrino driver only as a fallback for situations where it has not been able to load the acpi-cpufreq driver. Intel systems that can use the acpi-cpufreq driver no longer load the speedstep-centrino driver, and now handle P-states correctly. (BZ#485480)
  • a development version of this package attempted to make cpuspeed run reliably on Xen kernels by only allowing cpuspeed to start on Xen kernels if the number of virtual CPUs in dom0 equalled the number of physical CPUs in the system. However, this condition can never be true until xend starts, and xend starts after cpuspeed. Therefore, cpuspeed would only run properly on Xen kernels if cpuspeed were restarted after the system completed the boot process. The restriction that cpuspeed can only start if the number of virtual and physical kernels are equal has therefore been removed, allowing cpuspeed to start on Xen kernels even when xend has not yet started. (BZ#488924 , BZ#498406 , BZ#492139)

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