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Knut Anders Hatlen closed DERBY-2878. ------------------------------------- > Scan protection handle could be cached in BasePage > -------------------------------------------------- > > Key: DERBY-2878 > URL: https://issues.apache.org/jira/browse/DERBY-2878 > Project: Derby > Issue Type: Improvement > Components: Performance, Store > Affects Versions: 10.4.0.0 > Reporter: Knut Anders Hatlen > Assignee: Knut Anders Hatlen > Priority: Minor > Fix For: 10.4.0.0 > > Attachments: derby-2878-1.diff, derby-2878-1.stat, > derby-2878-1b.diff, derby-2878-2.diff, derby-2878-3.diff, derby-2878-3.stat, > derby-2878-3a.diff > > > Each time a leaf node in a B-tree is visited in an index scan, a scan > protection row is locked and unlocked. Both the lock operation and the unlock > operation will allocate a new RecordId object representing the scan > protection row (the unlock operation additionally allocates a PageKey object > for the RecordId). Since the scan protection handle created will be identical > (seen from equals()) each time it is created for a page, it would make sense > to cache it in BasePage. Then we only need to allocate the protection handle > for a page once for as long as it stays in the page cache. This would save > three object allocations per single-record lookup via index. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.