Open jyundt opened 7 years ago
A linked issue against Genesis should be created, to add/update a task to disable speed stepping before lshw collection.
So, collins only stores the CPU speed for the first socket, and only in one dimension? (i.e. CPU_SPEED_GHZ[0]). I wonder if there would be benefit of using dimensionality of tags to represent these values.
A linked issue against Genesis should be created, to add/update a task to disable speed stepping before lshw collection.
Will do, I can probably get a PR submitted for this as well.
So, collins only stores the CPU speed for the first socket, and only in one dimension? (i.e. CPU_SPEED_GHZ[0]). I wonder if there would be benefit of using dimensionality of tags to represent these values.
Ugh, I think I have this flipped, it's CPU[N] (the last CPU) that will be stored, not CPU[0]. Sorry for the confusion. I just verified by modifying an lshw XML dump with different product/vendor/speed information and inserting the node into collins.
I don't really have a strong preference on this dimensionality either way. Ideally all CPUs should be identical, however this speed stepping tripped us up.
During new asset inductions, only CPU information for the first socket is persisted. CPU information for sockets 2 - N is discarded.
As an example, given the following CPU information from LSHW, only CPU id 0 will be saved to the database. Note the differences between CPU speed:
As a result of this behavior, collins will drop information from the second socket:
This problem originally manifested itself while troubleshooting failing lshw XML tests: https://github.com/tumblr/collins/pull/537#discussion_r117804273. We noticed that our servers were reporting different CPU speeds on different sockets as a result of dynamic frequency scaling. This caused tests in
LshwHelperSpec
to consistently fail.As pointed out during the discussion in #537, a more appropriate fix would probably involve disabling dynamic frequency scaling in genesis to avoid different CPU speeds on different sockets.
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