[ZODB-Dev] Relstorage and over growing database.

[Shane Hathaway]

On 02/07/2013 01:54 PM, Jürgen Herrmann wrote:
> Am 07.02.2013 21:18, schrieb Jürgen Herrmann:
>> I know that's entirely not your fault but may be worth mentioning
>> in the docs. Relstorage with MySQL works *very* well for DB sizes
>> <5GB or so, above that - not so much :/
>
> Also for the docs: on disk Restorage/MySQL uses 4x the size of a
> FileStorage with same contents. As packing tables are filled this
> grows by another factor of ~2. If you don't pack very regularly
> you might up ending in DBs that donb't permit packing anymore
> because of the big size very quickly.

I suspect there are ways to fix all of that in the MySQL configuration. 
Like any SQL database, MySQL needs tuning as it grows.  Meanwhile, 
FileStorage doesn't really have any knobs, and it always stores in a 
fairly optimal way, so it's easier to use.

FileStorage has a couple of issues that often drive people to 
RelStorage: (1) the on-disk format is unique to FileStorage, and there 
aren't many tools available for analyzing and fixing a broken Data.fs. 
(2) FileStorage only supports multiple clients through ZEO, which has 
relatively high latency.  If these issues don't impact you, then 
FileStorage is clearly the better choice for you.

Shane