I can't help much, but I do remember reading that the records are padded with space. You can find that info here (towards the bottom).
http://orientdb.com/docs/2.1/plocal-storage-engine.html I know this kind of "pre-allocation" technique is necessary to allow for flexible schema i.e. adding properties to records later on or updating records with more data than was there before. As I understand the reason for record "pre-allocation", it is needed because, if the space taken by the record would be exactly the size of the record, then adding data to it (making the record size larger) would cause the database to have to move the record on disk, instead of updating it directly. You can imagine, if you then update a lot of records this way, you'd end up with a huge mess fast and the database would slow down considerably. So, in order to avoid that, the database pre-allocates space per record. ODB has the setting RECORD_GROW_FACTOR. In MongoDB, they recommend and set as default what they call "powersOfTwo". In other words, the database doubles the initial size of the document on disk. This is what is explained in the example in the docs. As I take it from the docs, the settings for record size can be changed through configuration. If you know your record size will never change, you could drop the values to "1". However, I could imagine, if you do that and then you do update and increase the data even a little in a good number of records, that will not jive well with the database. Though, I am no expert on that. I'd also like to know the overhead values of the data types otherwise. Would be great basic knowledge of the database. If one of the nice gents from Orient would lay it out here, I'd be even glad to add it to the documentation. It would be a great addition to this table: http://orientdb.com/docs/latest/Types.html Scott -- --- You received this message because you are subscribed to the Google Groups "OrientDB" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
