Makina-Corpus.Org

Last week i have made a rush to improve performance of a Plone based web site. For performance testing i have used JMeter, because i have seen Using open source tools for performance testing

JMeter is really nice to use. Just launch it’s proxy, plug your browser on it, and do your test. Next you save it as xml and you can edit the test. So you can login (it support cookies) you can create content (with an once logic controller) consult content, and stress your server.

What i have learn from this about Plone is:

• Do not use brains or any object in templates, or you will not beeing able to cache your logic code in ramcache. Use dict that contains every strings ready to be displayed in the templates.
• How to use the ram cache
• i can store acl_users in ramcache, and i have been surprised to see the difference. On 5 tabs hitted, i have hit the cache 278 times …
• Archetypes is damly slow (about one second to set some attributes of an object in a btree and reindexIt)
• CMFPlone.utils.createObjectByType do a reindexObject
• Do not add any index to the portal_catalog, use the buinding done by archetype_tool to be able to use other index. I m adding about one catalog tool per custom content type.
• A query on the portal_catalog can take one second if you have for example a list of 100 paths (query['path'] = ['/first/path', '/second/path'] and more than 100 000 entries.

I have learn many other things during the last week, but now i m using stress tests during the dev

First of all I would like to thank guys who wrote GenericSetup. I m writing this post cause i think profiles are not well used. They are used like Extensions/Install.py scripts. So what is a profile, and how to use it ?

Profile is about configuration of portals (portal_xxx inside the zmi). In that way I have started by asking myself “what means install/uninstall in Plone” ? Some answers:

• “its about the Extensions/install.py scripts.”
• “Like on your computer, you install a software or a lib”

Well, there is no sens for the word “install” in the world of plone. We are speaking about configuration of tools. So the CMFPlone/profiles/defaults, contains a plone default configuration. Right ?

In that way extending default plone configuration means, change it a bit, adding some directory views in portal_skins for example.

What happens if you are “installing” 20 products to you configuration ? Here it is ! You have lost the configuration of your Plone project and will not be able to understand why this new product you are trying to install break your website.

Seeing this, I have proposed to add one single profile by project. In that way you controle your entire Plone, and if you have a problem, you just have to apply this profile. But that also means you have to write it. Here is how i proceed:

• Install every product you need
• Export all steps
• Adding a new product/egg specially for your project
• Put the results of the exports in it
• Read it,
• Add all constraints in it. For example the order of layers inside skins.xml

This is done, you get it ! There is no duplication of files, but integration of products inside Plone configuration (my work). Writing XML is boring ? Writing them faster by using my eclipse templates ;)

The next point is about setup handlers. I hate product that add setup handler just to say “hey i know how to add a step”. I always ask for “what is a step for you ?” So steps are not the way to call a python script. If you are tented to add a step, just use Extension/install.py to put your script. Adding a step make sens only if you are adding a tools, and you want that tools to be configurable. So you don’t add setuphandler.py but you write import/export.py for your tool, and then you adding the step with import_step.xml.
An other problem is the configuration of your Plone project can be different for a production server and developpement local server. For example the mailhost.xml file can be different. In that way you can extend your profile with just a smaller profile that reconfigure what you need.

This is why i m laughing when i heard “uninstall profile”.

Finally, i don’t understand why the portal_quickinstaller is now “aware” of extensions profile. That doesn t help to understand profiles. People will continue to write install/uninstall profiles. If any one know why i m ready to discuss about it.