The wording is subtle and can be confusing... It's important to distinguish between: 1. "You need to start and complete a repair within any gc_grace_seconds window" 2. "You need to start and complete a repair within gc_grace_seconds"
#1 is a sliding time window for any time interval in which the tombstone (tombstone_created_time is written and the expiration of it (tombstoned_created_time + gc_grace_seconds) #2 is a duration bound for the repair time My post is saying that to ensure the #1 requirement, you actually need to "start and complete two consecutive repairs within gc_grace_seconds" On Fri, May 16, 2025 at 2:49 PM Mike Sun <m...@msun.io> wrote: > > You need to *start and complete* a repair within any gc_grace_seconds > window. > Exactly this. And since "any gc_grace_seconds" does not mean "any > gc_grace_window from which a repair starts"... the requirement needs to be > that the duration to "start and complete" two consecutive full repairs is > within gc_grace_seconds"... that will ensure a repair "starts and > completes" within "any gc_grace_seconds" window > > > > On Fri, May 16, 2025 at 2:43 PM Mick Semb Wever <m...@apache.org> wrote: > >> . >> >> >>> e.g., assume gc_grace_seconds=10 days, a repair takes 5 days to run >>> * Day 0: Repair 1 starts and processes token A >>> * Day 1: Token A is deleted resulting in Tombstone A that will expire on >>> Day 11 >>> * Day 5: Repair 1 completes >>> * Day 7: Repair 2 starts >>> * Day 11: Tombstone A expires without being repaired >>> * Day 12: Repair 2 repairs Token A and completes >>> >> >> >> You need to *start and complete* a repair within any gc_grace_seconds >> window. >> In your example no repair started and completed in the Day 1-11 window. >> >> We do need to word this better, thanks for pointing it out Mike. >> >
