converting a site to Pressflow

1. do a quick Diff of pressflow and vanilla and you'll see what the differences are. From what i remember there are very few schema changes, so you very well might be ok converting from d5 to d6 pressflow without issue, doing the diff will give a quick reference of what is changed and will help you overall grok problems and be able to isolate them as pressflow or drupal problems.

2. I would imagine the most difficult part of the transition will be CCK if the upgrade paths don't work for you consider using http://drupal.org/project/migrate It might be simpler to treat the d5 site as something totally foreign instead of troubleshooting the upgrade.

Thanks to @mizru and @dalin for your input. I've already gone ahead with the upgrade. It's been a bear, mostly because of (a) the length of time it takes to reload the database, and (b) the time it takes to drop and create each index - done by mySQL as inefficiently as possible (http://lists.mysql.com/mysql/202489).

I didn't create this app; I inherited it. I noticed that while most of the tables are myISAM, a handful are innoDB. This suggests to me that the previous developers (or their database admin) was aware of the differences between myISAM and innoDB and consciously chose to use a mixed strategy that he or she considered optimal. Since this is the first time in my long career as a developer that I've had to dabble in database optimization and performance, I'm giving them the benefit of a doubt.

So with the exception of all the "cache_" tables, which I've converted to innoDB to allow concurrent reads and writes, I'm leaving everything else as my predecessors set it up - at least until I have compelling evidence that it will pay to do otherwise.

Since PressFlow is optimized for innoDB, that pretty much precludes PressFlow for now. I'm betting that there will still be oportunities for database and PHP optimization.

Hi: I have been trying to upgrade a site from Acquia Drupal 6.20 to Pressflow 6.20. My first approach was to just delete and replace the core Drupal modules with those from the Pressflow distribution 6.20.97.

The site comes up but then when I run an update I get an odd looking update screen with a bunch of select variables rather than the normal screen. It appears to be running an update successfully however. When finished, I can load my site BUT all my Views have vanished.

So, I flushed caches and checked permissions after rebuilding them and it does not appear to be that. I can see the Views UI and all my Views are listed there. But when I run a preview of any of them nothing is returned by the preview. And no View appears in the various blocks and pages where they are supposed to occur.

I have repeated all this several times and get the same result. I cant find any helpful tips in the Drupal sites.

My server is an Acquia dev cloud instance. It says it is running MySql 5.0.51a and PHP 5.2.4-2ubuntu5.14

In case it is relevant I have kept the folder called Acquia in the modules folder, where it contains various contributed modules from the Acquia distribution that are in use. In theory that would be better in the sites/all/modules location but I am not sure how to move it without screwing up the database.

I would really welcome any ideas or suggestions.

Sorry about posting in the wrong place, but thanks for the reply. I am a newbie.

I think I did what you said in essence. My Drupal installation was in my home folder. I replaced all the other files in there too (from the Pressflow distribution) eg cron.php, index.php etc.

Have I missed something do you think? My reason for posting is that it did not seem to quite work as a drop in and I cannot figure out how to troubleshoot.

Thanks for the above. For anyone who finds this problem, I found that the modules Scribe SEO, and userpoints_reset and user_points_retroactive all caused major problems with my Pressflow upgrade. Balance_tracker seemed possibly suspect too.