[ZODB-Dev] filestorage open latency

[Neil Schemenauer]

On Wed, Dec 11, 2002 at 12:43:53PM -0800, David McCusker wrote:
> The recent commentary on profiling open time for filestorage databases
> suggests opening a zodb database has significant latency on the order
> of a couple or more dozens of seconds.

If you use ZEO then that overhead goes away since connecting to a ZEO
server is quick.  For serious applications I think you really want to
use ZEO.

> Is that inherent in the filestorage architecture?

Not really.  AFAIK, the delay is due to consistency checks and loading
of the OID index.  The consistency checks could be disabled and the
index data could be loaded on demand instead of at startup.

> Is open latency for Berkeley db stores less?

I have little knowledge of the Berkeley db storage.

> Do all zodb stores support undo?

No.

> If only filestorage supports undo, is it necessary to accept open
> latency in order to get undo?

No.

  Neil