Relaxing consistency detection to include errors while inserting to memtable as WAL recovery error.

Summary: The current code, considers data to be consistent if the record
checksum passes. We do have customer issues where the record checksum passed but
the data was incomprehensible. There is no way to get out of this error case
since all WAL recovery model will consider this error as unrelated to WAL.

Relaxing the definition and including errors while inserting to memtable as WAL
errors and handing them as per the recovery level.

Test Plan: Used customer dump to verify the fix for different level. The db
opens for kSkipAnyCorruptedRecords and kPointInTimeRecovery, but fails for
kAbsoluteConsistency and kTolerateCorruptedTailRecords.

Reviewers: sdon igor

CC: leveldb@

Task ID: #7918721

Blame Rev:

db/db_impl.cc

@@ -1148,8 +1148,12 @@ Status DBImpl::RecoverLogFiles(const std::vector<uint64_t>& log_numbers,
 
       MaybeIgnoreError(&status);
       if (!status.ok()) {
-        return status;
+        // We are treating this as a failure while reading since we read valid
+        // blocks that do not form coherent data
+        reporter.Corruption(record.size(), status);
+        continue;
       }
+
       const SequenceNumber last_seq = WriteBatchInternal::Sequence(&batch) +
                                       WriteBatchInternal::Count(&batch) - 1;
       if ((*max_sequence == kMaxSequenceNumber) || (last_seq > *max_sequence)) {
@@ -1183,12 +1187,11 @@ Status DBImpl::RecoverLogFiles(const std::vector<uint64_t>& log_numbers,
     }
 
     if (!status.ok()) {
-      // The hook function is designed to ignore all IO errors from reader
-      // during recovery for kSkipAnyCorruptedRecords. Status variable is
-      // unmodified by the reader.
-      assert(db_options_.wal_recovery_mode !=
-             WALRecoveryMode::kSkipAnyCorruptedRecords);
       if (db_options_.wal_recovery_mode ==
+             WALRecoveryMode::kSkipAnyCorruptedRecords) {
+        // We should ignore all errors unconditionally
+        status = Status::OK();
+      } else if (db_options_.wal_recovery_mode ==
                  WALRecoveryMode::kPointInTimeRecovery) {
         // We should ignore the error but not continue replaying
         status = Status::OK();
@@ -1197,8 +1200,11 @@ Status DBImpl::RecoverLogFiles(const std::vector<uint64_t>& log_numbers,
         Log(InfoLogLevel::INFO_LEVEL, db_options_.info_log,
             "Point in time recovered to log #%" PRIu64 " seq #%" PRIu64,
             log_number, *max_sequence);
-      } else if (db_options_.wal_recovery_mode !=
-                 WALRecoveryMode::kSkipAnyCorruptedRecords) {
+      } else {
+        assert(db_options_.wal_recovery_mode ==
+                  WALRecoveryMode::kTolerateCorruptedTailRecords
+               || db_options_.wal_recovery_mode ==
+                  WALRecoveryMode::kAbsoluteConsistency);
         return status;
       }
     }