mds: fix dropping events in standby replay #12077
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| dout(10) << " segment seq=" << seg->seq << " " << seg->offset << | ||
| "~" << seg->end - seg->offset << dendl; | ||
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| if (seg->end > journaler->get_read_pos()) { |
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seg->end is set to journaler->get_read_pos() after reading each log event. How can this test be true?
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You're right, I wrote this branch when experimenting and forgot to remove it. The "segments.size() == 1" below is the part that really fixes the bug.
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@ukernel does it look good now? |
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If I understand the code correctly. The code tries trimming all segments except the head one. This seems incorrect. (If a log segment is not expired by active MDS, updates in the segment haven't |
Ensure that we never drop the last segment during standby replay -- this avoids the case where we start ignoring events because we think we're still waiting to see a subtreemap. Fixes: http://tracker.ceph.com/issues/17954 Signed-off-by: John Spray <john.spray@redhat.com>
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Sorry, I messed this up when committing it. I originally mean to remove the "seg->end > journaler->get_read_pos()" condition and leave the "seg->end > expire_pos" condition, but I removed the wrong one. As you say, the expire_pos check still needs to be there. |
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(it's fixed now) |
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Reviewed-by: Yan, Zheng zyan@redhat.com |
Ensure that we never drop the last segment during
standby replay -- this avoids the case where we
start ignoring events because we think we're
still waiting to see a subtreemap.
Fixes: http://tracker.ceph.com/issues/17954
Signed-off-by: John Spray john.spray@redhat.com