If you are concerned that your Plone site will grow up to be a fatty, you need to seriously consider upfront.diet. upfront.diet is a collection of fat burning code snippets and disciplines that will keep your Plone site fit and in shape. If you want to write Plone apps that need to scale to millions of objects, you'll need a fundamental understanding of what is inside each pickle in the ZODB. This talk will go over the fundamentals and explore the tools that abstract it right away so that you can forget about it, and focus on development.

1. upfront diet for plone
Roché Compaan

3. About me
● Owner of Upfront Systems
● Founded Upfront Systems in 1998
● Zope developer for the past 10 years

4. Experience
● Largest Plone deployments to date: 5FM & MetroFM
● 5FM
– 20 million page views per month
– 70 thousand members
– 6 million objects in ZODB
● Metro FM
– 15 million page views per month
– 20 thousand members
– 2 million objects in ZODB
● Helping Connexions with performance
● http://www.markhorner.net/2010/04/29/connexions-authoring-
performance/

7. Can Plone scale to 10 million documents?

8. ZODB Benchmarks
● Most common myth spread: “ZODB is a high
read, (s)low write database”
● No published ZODB benchmarks
● Wrote some benchmarks that test ZODB
read/write speed in 2008
● collective.zodbbench

9. ZODB Write Speed
0 500 thousand 2,5 million 5 million 7,5 million 8,5 million 10 million
0
1000
2000
3000
4000
5000
6000
7000
8000
Postgres
ZODB
Number of records
Inserts/second

10. ZODB Lookup Speed
Number of Objects Lookup Time
100,000 0.003 ms
1,000,000 0.006 ms
10,000,000 2 ms

11. Benchmark Conclusions
● Thanks Jim, ZODB Rocks!
● Large cache size important for writes too, not
only reads
● Need a solution for more than 10 million objects
● If the ZODB can handle 250 inserts/second at
peak volume why does it take a full minute to
add 250 ATDocuments?

12. A closer look at Plone
● Added 10,000 documents to Plone, while
profiling with Dieter Maurer's ZopeProfiler
● Timed “apply_index” method to find indexes
performing badly with and without
experimental.catalogqueryplan
● Batch import of content with an without
references.
● Used fsdump to inspect pickle contents.

13. Plone Benchmark Conclusions
● portal_catalog remains a bottleneck to scaling a
Plone site.
● 1 catalog == many many conflicts
● reference_catalog is a major performance
bottleneck
● Indexing 10,000 documents shows that 90% of
the objects in Data.fs relate to indexing.

14. What's in a pickle?
2,51755
81,564
9,872
20,024
85
655
1,544
30,455
182,708
7798,088122
Pickle contents of a single transaction adding an ATDocument
object size in bytes
IIBTree
Folder
IOBucket
OIBucket
IIBucket
IOBTree
BTrees.Length
ATDocument
OOBTree
IISet
Archetypes.BaseUnit
OOBucket
IITreeSet

15. Think before you index!
“Waking up objects is expensive” - this is an
irrational fear. And adding another catalog in
response to this fear requires therapy.

16. The portal_catalog problem
● No navigation, portal tabs, folder contents, review
queue if your content type is not in the portal_catalog.
● Your content type is automatically subscribed to 20+
indexes in the portal_catalog. Bad for new developers
with hopes of building an enterprise CMS.
● Unless you have 5+ years experience with Zope – it's
not so easy to “opt out”
● portal_catalog should only be used for content
searches – no functionality must depend on it.

17. What is upfront.diet?
● It's a healthier and happier approach to Plone
development: index only when you really really need
to.
● Set of packages that re-implement plone functionality
without depending on the portal_catalog and
reference_catalog.
● Includes replacements for: portal tabs, navigation
portlet, folder contents, archetype references.
● Provides a catalog blacklist/whitelist to customise
indexing per content type.

18. More about upfront.diet
● upfront.navportlet
● Separate catalog for navportlet
● upfront.simplereferencefield
●
Store references directly on object using annotations
● still depends uid_catalog
● upfront.foldercontents
● Adapter for IFolderish
● Index allowedRolesAndUsers directly on folder – less conflicts
● upfront.catalogblacklist
● Generic Setup profile with a whitelist and blacklist of indexes per
content type
● patches IndexableObjectWrapper, ugh!

19. upfront.diet todo list
● Packages:
● Portal tabs (done but not a separate package yet)
● Sitemap
● Review queue
● News and Events Smart Folders
● Site Search
● References without uid_catalog
● Comparative benchmarks with and without it

20. upfront.diet deployments
● Very few at the moment but looks promising
● Fullmarks.org.za (half a million objects, Data.fs
< 1GB)

21. Contact Me
● Email: roche@upfrontsystems.co.za
● Blog:
http://upfrontsystems.co.za/Members/roche
● facebook.com/rochecompaan
● twitter.com/rochecompaan

22. Questions?