[Plugin: Collapsing Categories] custom permalink slow site!

Hello
Finally found why my site was slow.
I just want to share with everyone what i found recently why my site was slow,i discovered yesterday during organizing categories and posts.

The problem was in permalink structure i was using custom permalink /%category%/%postname%/ and in combination with Collapsing Categories plugin which allow me to add a widget on every page with all my categories and posts it was causing my site to load page very slow,so i have set permalink to Post name /sample-post/ and the site was like before loading fast even with Collapsing Categories widget that i use.

Hope this helps someone.