Re: over 128MB usage and 96% cpu usage
Large pages will consume more resources. With the various manipulations, Tiki ends up having multiple copies of the content in memory. PHP also has a overhead of memory management.
Tiki improved memory usage significantly with recent releases, but it mostly affect the page views. Writes are generally heavy processes to make sure the reads can be efficient. PHP also has improvements with later versions and Tiki 12 runs smoothly over PHP 5.5.
User watches may be your issue. They are known to be hungry and are being redesigned for Tiki 13. However, it might not help your case with large pages.
There are a few rules of thumb about high memory usage, like the calendar module being extremely heavy, but when it comes to figuring out what the issue really is, there is nothing quite like profiling the application. This cannot be done on the server as you need additional developer tools.
Which version of Tiki are you using?
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