Sorry, the code format of previous email is error , I reedit the code format :




When I look the code of Index.preWALRestore method, I find 
RecoveryIndexWriter.write method is used to write the indexUpdates in following 
line 565:


547   @Override
548   public void preWALRestore(ObserverContext<RegionCoprocessorEnvironment> 
env, HRegionInfo info,
549       HLogKey logKey, WALEdit logEdit) throws IOException {
550       if (this.disabled) {
551          super.preWALRestore(env, info, logKey, logEdit);
552          return;
553        }
554    // TODO check the regions in transition. If the server on which the 
region lives is this one,
555    // then we should rety that write later in postOpen.
556    // we might be able to get even smarter here and pre-split the edits 
that are server-local
557    // into their own recovered.edits file. This then lets us do a 
straightforward recovery of each
558    // region (and more efficiently as we aren't writing quite as hectically 
from this one place).
559
560    /*
561     * Basically, we let the index regions recover for a little whilelong 
before retrying in the
562     * hopes they come up before the primary table finishes.
563     */
564    Collection<Pair<Mutation, byte[]>> indexUpdates = 
extractIndexUpdate(logEdit);
565    recoveryWriter.write(indexUpdates, true);
566  }




but the RecoveryIndexWriter.write method is as following, it directly throws 
Exception except non-existing tables, so RecoveryIndexWriter's 
failurePolicy(which is StoreFailuresInCachePolicy by default) even has no 
opportunity to be used, and it leads to Index.failedIndexEdits which is filled 
by the StoreFailuresInCachePolicy is always empty.


 @Override
    public void write(Collection<Pair<Mutation, byte[]>> toWrite, boolean 
allowLocalUpdates) throws IOException {
        try {
            write(resolveTableReferences(toWrite), allowLocalUpdates);
        } catch (MultiIndexWriteFailureException e) {
            for (HTableInterfaceReference table : e.getFailedTables()) {
                if (!admin.tableExists(table.getTableName())) {
                    LOG.warn("Failure due to non existing table: " + 
table.getTableName());
                    nonExistingTablesList.add(table);
                } else {
                    throw e;
                }
            }
        }
    }


So the Index.postOpen method seems useless,because the updates Multimap in 
following 522 line which is geted from Index.failedIndexEdits is always empty.


520  @Override
521  public void postOpen(final ObserverContext<RegionCoprocessorEnvironment> 
c) {
522    Multimap<HTableInterfaceReference, Mutation> updates = 
failedIndexEdits.getEdits(c.getEnvironment().getRegion());
523    
524    if (this.disabled) {
525        super.postOpen(c);
526        return;
527      }
528   LOG.info("Found some outstanding index updates that didn't succeed during"
529        + " WAL replay - attempting to replay now.");
530    //if we have no pending edits to complete, then we are done
531    if (updates == null || updates.size() == 0) {
532      return;
533    }
534    
535    // do the usual writer stuff, killing the server again, if we can't 
manage to make the index
536    // writes succeed again
537    try {
538        writer.writeAndKillYourselfOnFailure(updates, true);
539    } catch (IOException e) {
540            LOG.error("During WAL replay of outstanding index updates, "
541                    + "Exception is thrown instead of killing server during 
index writing", e);
542    }
543  }


I think in Index.preWALRestore method, we should use 
RecoveryWriter.writeAndKillYourselfOnFailure method to write the indexUpdates, 
not the RecoveryIndexWriter.write method.




 

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