About a month ago I was 5 minutes late for a #skillsmatter event, a talk on #neo4j and mechanical sympathy. The talk was given by a #neo4j employee, thus given by someone in-the-know.
Because of my tardiness I missed why neo4j is mechanically sympathetic; the whole point of the talk. I should have had a chat with the presenter after the talk to clear up my lack of understanding, however the Slaughtered Lamb is not as conducive to conversation as it once was...
Are we saying that neo4j is mechanically sympathetic in terms of the records being powers of 2, or that the talk allows us to understand how neo4j works in the same way that Jackie Stewart knew how his cars worked because he had previously worked as a mechanic? I'm guessing the later as the neo4j cheat sheet shows records as 5, 9, 25 and 33 bytes, not exactly powers of 2.
A question came up during the session about the how many nodes you could have; the maximum NodeRecordIdSize. The response was that it wasn't 4 bytes as shown on the cheat sheet, but 4 bytes, plus 7 bits. The suggestion was that you could use the 7 'spare' bits of the 'in use' byte as only 1 bit of this byte is actually used.
With that said, my questions is, how would that affect the 4 byte reference allocation in, for instance, the RelationshipRecord, which is only allocated 4 bytes? Where are the 7 'spare bits' stored?