array_block_size is bugged in 2.3.1

[rickardoberg]

In Neo4j Community 2.3.1, if I start a database with array_block_size set and then create nodes with large strings and byte arrays, reading the database will fail. Seems like the dynamic string store also uses the array_block_size setting for reading, but not when creating records, so you get InvalidRecordExceptions.

Workaround: set string_array_size to same as array_block_size. Records will now be created with same size, so reading does not crash.

Minimal test case attached.
ArrayBlockSizeBugTest.java.zip

[rickardoberg]

Ok, found the problem:
https://github.com/neo4j/neo4j/blob/2.3/community/kernel/src/main/java/org/neo4j/kernel/impl/api/store/StorePropertyPayloadCursor.java#L259

The method can get string or array store, but only keeps one cursor. It should keep one per store. Now if I first read from array store, that cursor will be assigned, and then if I read a string the array store cursor will be reused, which fails with InvalidRecordException. There needs to be one cached cursor per store, basically.

[spacecowboy]

Thanks, I added a Trello card.