[GEODE-5557] enabling read conflict detection may cause transactions to fail with a conflict on entries that are never written

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.0.0-incubating
• Fix Version/s: 1.10.0
• Component/s: transactions
• Labels: SmallFeature needs-review pull-request-available
• Assignee: Mario Ivanac
• Reporter: Darrel Schneider
• Created: 09/Aug/18 21:17
• Updated: 26/Sep/19 18:03
• Resolved: 11/Jul/19 18:31

Description

Read conflict detection can be enabled with -Dgemfire.detectReadConflicts=true.

If this is done then a transaction can fail because it read an entry that some one else modified.

But it is possible that this feature will cause your transaction to fail because some other transaction read an entry that you read or wrote. These are not valid conflicts.

This bug is caused by the way TXReservationMgr checks for conflicts. It treats every key sent to it as if it was written and when read confliction detection is enabled keys we only read are sent to it.

Issue Links

• duplicates: GEODE-5486 Two transactions with only read operations produce CommitConflictException if property gemfire.detectReadConflict=true
• links to: GitHub Pull Request #3492