Ensure that monotonic clocks really are monotonic #199
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Resuming wizened snapshots means that clocks don't necessarily stay monotonic. This patch overrides `clock_gettime` to address that, by adding an offset determined at the end of wizening. Signed-off-by: Till Schneidereit <[email protected]>
guybedford
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Jan 20, 2025
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Makes sense. If running on machines in different timezones, I wonder if we should also be doing a similar thing for the real time instead with a lower bound as opposed to an offset.
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I don't think we need to do anything about the realtime clock: that is expected to vary, and in particular the timezone can change at any point even on one computer. |
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Resuming wizened snapshots means that clocks don't necessarily stay monotonic. This patch overrides
clock_gettimeto address that, by adding an offset determined at the end of wizening.@andreiltd, this should fix the assert you encountered in #190, and hopefully allow us to do better on validating our GC rooting.