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[fix][compaction] Rowset::end_version null pointer #9379

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Merged
yiguolei merged 1 commit into from
May 6, 2022
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[fix][compaction] Rowset::end_version null pointer #9379

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7 changes: 6 additions & 1 deletion be/src/olap/compaction.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -136,7 +136,12 @@ Status Compaction::do_compaction_impl(int64_t permits) {
int64_t current_max_version;
{
std::shared_lock rdlock(_tablet->get_header_lock());
current_max_version = _tablet->rowset_with_max_version()->end_version();
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@yiguolei yiguolei May 5, 2022

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when will rowset_with_max_version == nullptr?

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@xinyiZzz xinyiZzz May 5, 2022 •
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This seems to happen in two cases:

  1. The tablet has no rowset.
  2. The version of max version rowset no longer exists in the tablet.

In fact, I did not carefully analyze why it occurs. Because other tablet->rowset_with_max_version() all compare whether the return value is null, so I also compare here : )

And here current_max_version is only used to print the log, it will not affect the execution.

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@yiguolei yiguolei May 5, 2022

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  1. The tablet should not have rowset because when the table is created BE will add 0-1 rowset to the tablet.
  2. I think we should be careful with this case... Maybe should deep dive some code.

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@xinyiZzz xinyiZzz May 5, 2022

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  1. The tablet should not have rowset because when the table is created BE will add 0-1 rowset to the tablet.
  2. I think we should be careful with this case... Maybe should deep dive some code.

I agree, these two cases are not normal, maybe the tablet was deleted during compaction, or invalid?

At present this is the previous solution, there may be a better way.

RowsetSharedPtr max_rowset = _tablet->rowset_with_max_version();
if (max_rowset == nullptr) {
current_max_version = -1;
} else {
current_max_version = _tablet->rowset_with_max_version()->end_version();
}
}

LOG(INFO) << "succeed to do " << merge_type << compaction_name()
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