[ZOOKEEPER-387] closeLedger shouldn't shut down all QuorumEngines

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Duplicate
• Component/s: contrib-bookkeeper
• Assignee: Flavio Paiva Junqueira
• Reporter: Flavio Paiva Junqueira
• Created: 29/Apr/09 08:32
• Updated: 04/May/09 15:02
• Resolved: 04/May/09 15:02

Description

We had initially assumed one ledger open at a time, and LedgerRecoverMonitor reads and closes a ledger without instantiating a QuorumEngine. Consequently, when closing a ledger, we have to shut down a QuorumEngine only if there is one. A poor way of implementing it is by having a for loop that iterates over all available QuorumEngines and shut them down. Given the assumptions of one ledger at a time and no QuorumEngine for LedgerRecoveryMonitor, this implementation works. However, as we move to a more flexible model in which multiple ledgers can be open and closed at arbitrary times, the for loop choice no longer works.

The attached patch fixes this problem by just shutting down the QuorumEngine instance corresponding to the ledger being closed, and it checks if a QuorumEngine exists before submitting a STOP operation. The patch also includes a test that opens four ledger, and then sequentially writes to the each ledger and closes it.

Issue Links

• is part of: ZOOKEEPER-380 bookkeeper should have a streaming api so that its easier to store checpoints/snapshots in bookkeeper.