Do not log unnecessary WAL obsoletion events (#7765)

Summary:
min_wal_number_to_keep should not be decreasing, if it does not increase, then there is no need to log the WAL obsoletions in MANIFEST since a previous one has been logged.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7765

Test Plan: watch existing tests and stress tests to pass

Reviewed By: pdillinger

Differential Revision: D25462542

Pulled By: cheng-chang

fbshipit-source-id: 0085fcb6edf5cf2b0fc32f9932a7566f508768ff
This commit is contained in:
Cheng Chang 2020-12-10 12:54:34 -08:00 committed by Facebook GitHub Bot
parent 40f2b65008
commit fd7d8dc56e

View File

@ -481,17 +481,21 @@ Status MemTableList::TryInstallMemtableFlushResults(
// We piggyback the information of earliest log file to keep in the
// manifest entry for the last file flushed.
edit_list.back()->SetMinLogNumberToKeep(min_wal_number_to_keep);
} else {
min_wal_number_to_keep =
PrecomputeMinLogNumberToKeepNon2PC(vset, *cfd, edit_list);
}
std::unique_ptr<VersionEdit> wal_deletion;
if (vset->db_options()->track_and_verify_wals_in_manifest) {
if (!vset->db_options()->allow_2pc) {
min_wal_number_to_keep =
PrecomputeMinLogNumberToKeepNon2PC(vset, *cfd, edit_list);
}
if (min_wal_number_to_keep >
vset->GetWalSet().GetMinWalNumberToKeep()) {
wal_deletion.reset(new VersionEdit);
wal_deletion->DeleteWalsBefore(min_wal_number_to_keep);
edit_list.push_back(wal_deletion.get());
}
}
const auto manifest_write_cb = [this, cfd, batch_count, log_buffer,
to_delete, mu](const Status& status) {
@ -754,11 +758,13 @@ Status InstallMemtableAtomicFlushResults(
min_wal_number_to_keep =
PrecomputeMinLogNumberToKeepNon2PC(vset, cfds, edit_lists);
}
if (min_wal_number_to_keep > vset->GetWalSet().GetMinWalNumberToKeep()) {
wal_deletion.reset(new VersionEdit);
wal_deletion->DeleteWalsBefore(min_wal_number_to_keep);
edit_lists.back().push_back(wal_deletion.get());
++num_entries;
}
}
// Mark the version edits as an atomic group if the number of version edits
// exceeds 1.