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Boosted by cstanhope@social.coop ("Your weary 'net denizen"):
jaseg@chaos.social wrote:

Stopping the system fans to heat up the system to shift clock phase by a few femtoseconds is one of the less hinged ideas I’ve seen come out of CERN lol.

(AFAIU this was an experiment for a software retrofit to hardware otherwise incapable of such adjustments)

Slide with LHCb logo reading “Phase stabilization under hardware constraints Using the server internal fans to heat up and cool down the FPGA in order to shift the phase and stabilize it within a Std Dev of 1 ps.”. A larger text block follows, next to a graph showing clock phase against system temperature. The larger text block reads: Python script running a PID algorithm to read the phases and control the fans. At the left I set the script to different phase setpoints. (60, 70, 80 ps) The plateau in the middle is the phase shifter keeping the phase at 80ps even when the AC started oscillating the temperature up to 3C pk-pk. At the right end I turned off the script, which caused the phase to start shifting with the temperature again. Link to presentation at the 17th HPTD meetin