[BOOKKEEPER-501] Release topic does not close ledger causing unnecessary fence

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Won't Fix
• Component/s: bookkeeper-server, hedwig-server
• Assignee: Unassigned
• Reporter: Jiannan Wang
• Created: 11/Dec/12 21:47
• Updated: 16/Mar/16 04:21
• Resolved: 16/Mar/16 04:21

Description

We find lots of read entry error logs caused by fencing periodically.

We set hedwig server "retention_secs" to 2 days, so topics may be released after 2 days:

AbstractTopicManager#notifyListenersAndAddToOwnedTopics

scheduler.schedule(new Runnable() {
                        @Override
                        public void run() {
                            // Enqueue a release operation. (Recall that release
                            // doesn't "fail" even if the topic is missing.)
                            releaseTopic(topic, new Callback<Void>() {

                                @Override
                                public void operationFailed(Object ctx, PubSubException exception) {
                                    logger.error("failure that should never happen when periodically releasing topic "
                                                 + topic, exception);
                                }

                                @Override
                                public void operationFinished(Object ctx, Void resultOfOperation) {
                                    if (logger.isDebugEnabled()) {
                                        logger.debug("successful periodic release of topic "
                                            + topic.toStringUtf8());
                                    }
                                }

                            }, null);
                        }
                    }, cfg.getRetentionSecs(), TimeUnit.SECONDS);

And once topic is released, BookkeeperPersistenceManager#ReleaseOp will run and close all ledgers, but the BookkeeperPersistenceManager#closeLedger() do nothing (actually the close ledger code is commented):

BookkeeperPersistenceManager#closeLedger

    public void closeLedger(LedgerHandle lh) {
        // try {
        // lh.asyncClose(noOpCloseCallback, null);
        // } catch (InterruptedException e) {
        // logger.error(e);
        // Thread.currentThread().interrupt();
        // }
    }

So it will trigger fence operation when topic is acquired, which cause periodical unnecessary read entry error for recovery.

I think there are two improvement for this issue:
1. Close ledger when release topic.
2. read entry failed caused by fence should not be taken as an error.

Issue Links

• duplicates: BOOKKEEPER-192 Hub server should try to close ledgers when releasing topic or shutting down server
• relates to: BOOKKEEPER-275 [Log Improvement]: Error logs logged at the time of switch which is misleading