[Zope-dev] Massive scalability

John Eikenberry jae@kavi.com
Tue, 16 Jan 2001 19:11:45 -0800


Michael Bernstein wrote:

> John Eikenberry wrote:
> > 
> > I was looking into the same issues recently, but for a much smaller set of
> > data (50000ish). In my tests ZPatterns/binary-trees scaled well for storage
> > and retrieval. But ZCatalog did not. It was basically useless for partial
> > matching searches (taking many minutes for searches that retrieved more
> > than 100 matches)
> 
> Was this true even for cases where the batch size was
> smaller than 100? For example, if a search returns over 100
> results but the batch size is only 20 (so that only 20
> results at a time are displayed), do you still get the
> performance hit?

Short answer: yes 

Long answer: If you check out the source and/or hit it with the profiler
you'll see that the way the partial search works is to first do a more
general search then to limit the hits as much as possible via regex's.
Both these steps have to happen no matter the batch size, and this is where
you take the performance hit.  

> > [snip]
> > I ended up deciding to go with a RDBMS backend for data storage with a
> > ZPatterns interface. SkinScripts work so well for this that I'm actually
> > glad I switched. It simplified my design and implementation immensely.
> 
> So you're saying that you are doing all searching using SQL
> statements, and not just object retreival and storage,
> correct? How are you handling full text searches?

Yes. I'll use MySQL's built in pattern matching facilities. It can do full
text searches with partial matching, and it can do this fast.  I'm working
on a system that will return the DataSkin's in responce to the query.
Allowing me to deal with just the objects yet use all of MySQL's
facilities. 

I'v just started to work on this as part of a larger project, but I'm doing
it full time and should have something fairly soon. My company is very free
software friendly, so I'll be able to share it once its ready. If you
happen to be interested.

-- 

John Eikenberry
[jae@zhar.net - http://zhar.net]
______________________________________________________________
"A society that will trade a little liberty for a little order
 will deserve neither and lose both."
                                          --B. Franklin