[ZODB-Dev] Packing BIG fat Data.fs

[Jim Fulton]

Chris Withers wrote:
> 
> Jim Fulton wrote:
> >
> > We've had custmers routinely pack much larger databases.
> 
> How much RAM per MB of Data.fs would you expect a pack to use?

It's not RAM per MB, it's RAM per object. I'd say that you need about
300 bytes per object in the database, this is due to some in-memory
inbexes that FileStorage uses. The Berkeley database Full storage
that Barry Warsaw put together doesn't use in-memory indexes, and
should use a lot less memory.

Now, both stoages load one record at a time into
memory, so if you had a *really* big record, you could use a lot
of memory, but then it's hard to beleive you had enough memory
to write the record in the first place.

Jim

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