fix(v2): avoid starvation of failed jobs in the compaction scheduler #3732
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kolesnikovae
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simonswine
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Dec 2, 2024
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I've been testing various failure modes and discovered that it still possible for a job that has already been reassigned to starve and remain in the queue (this time, after the first unsuccessful retry). The reason is that we give up too early when traversing the queue:
In the chart, you can see that individual reassignments are handled as expected. However, it fails to process jobs after a subsequent failure, and the jobs get stuck in the
reassignedstatus without moving tofailed, nor are they retried repeatedly until the error threshold is exceeded.The fix is quite straightforward: inspect all the jobs eligible for reassignment. This, however, requires protection against the case where all jobs are getting reassigned (e.g., due to a bug or unavailability of the object store).