Update seq when merging deltas from partial log merge.#289
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Update seq when merging deltas from partial log merge.#289
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merge_read_item() fails to update found->seq when combining delta items from multiple finalized log trees. Add a test case to replicate the conditions of this issue. The conditions to get this to reproduce are pretty tricky. We have to exceed the block limit and that's nearly impossible at VM scale with out significant load. Or we can force a partial merge with a trigger, which is what this changeset does. Signed-off-by: Auke Kok <auke.kok@versity.com>
Two different clients can write delta's for totl indexes at the same time, recording their changes. When merged, a reader should apply both in order, and only once. To do so, the seq determines whether the delta has been applied already. The code fails to update the seq while walking the trees for deltas to apply. Subsequently, when processing subsequent trees, it could re-process deltas already applied. In case of a large negative delta (e.g. removal of large amounts of files), the totl value could become negative, resulting in quota lockout. The fix is simple: advance the seq when reading partial delta merges to avoid double counting. Signed-off-by: Auke Kok <auke.kok@versity.com>
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Two different clients can write delta's for totl indexes at the same time, recording their changes. When merged, a reader should apply both in order, and only once. To do so, the seq determines whether the delta has been applied already.
The code fails to update the seq while walking the trees for deltas to apply. Subsequently, when processing subsequent trees, it could re-process deltas already applied. In case of a large negative delta (e.g. removal of large amounts of files), the totl value could become negative, resulting in quota lockout.
The fix is simple: advance the seq when reading partial delta merges to avoid double counting.