Difference between revisions of "Cpuinfo"
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criu cpuinfo dump | criu cpuinfo dump | ||
− | to produce ''cpuinfo'' image file which consists of bits representing the capabilities current CPU | + | to produce ''cpuinfo'' image file which consists of the running CPU information and bits representing the supported capabilities. |
+ | |||
+ | == Testing CPU capabilities == | ||
+ | |||
+ | To check if the capabilities saved in ''cpuinfo'' image file is match to the current CPU one should run | ||
+ | |||
+ | criu cpuinfo check | ||
+ | |||
+ | == Checkpoint/Restore with CPU capabilities == | ||
+ | |||
+ | While by default CRIU does not save CPU capabilities in image file one can pass '''--cpu-cap''' option to force CRIU to save and check CPU capabilities on dump and restore accordingly. |
Revision as of 19:04, 11 November 2014
CPU capability problem
Because CRIU allows to live migrate containers (see Live migration for details) it might happen that CPU a container has been ran on differ from the target CPU. For typical programs this might be not a problem but if a program get compiled with optimization which use a particular CPU feature (say AVX instruction and etc) the lack of the feature on a destination machine will lead to execution exception in a best case.
Thus there should be a way to test if destination machine is capable of running container being migrated.
Saving CPU capabilities into an image file
CRIU does not write CPU capabilities into an image by default in a sake of speed. Instead one have to run CRIU as
criu cpuinfo dump
to produce cpuinfo image file which consists of the running CPU information and bits representing the supported capabilities.
Testing CPU capabilities
To check if the capabilities saved in cpuinfo image file is match to the current CPU one should run
criu cpuinfo check
Checkpoint/Restore with CPU capabilities
While by default CRIU does not save CPU capabilities in image file one can pass --cpu-cap option to force CRIU to save and check CPU capabilities on dump and restore accordingly.