Using transient for dynamic css , how to name it?

Question

I am thinking on using transient for my theme dynamic css in order to lower the site load.

Currently I have 15 php functions summed up in one collection function that do something like

 $css .= $element_name . '{color:'. esc_attr($value) .';}';

so basically just processors.

The collection function is outputted only once in the head so I thought of using transient for the output. Thing is that the css processing changes depending on page so I need to name my transient properly,

I was thinking about

'theme_name_temp_css'.get_queried_object_id()

but I am not sure if I can rely on get_queried_object_id() Are the ID's unique always or can it happen that 2 custom post types endup having same page ID 1 ?

Like portfolio and events.

To sum up,

Is get_queried_object_id() reliable to use with mixed post types ?

Would it be to much to use multiple transients ( for each wp page one ) ?

Should I use one transient for all pages ( an array )? It would be easier to remove it on theme settings change.

Answer 1

Unless you do something weird with your settings, transients will just make your code harder to read without adding any measurable performance value.

People that want performance should use object caching and page caching and your current code is probably already the best there is to utilize them. Transients will add almost nothing for them.

Transients make sense when you want to save several DB queries or network access, but your theme mods are already retrieved in one query from the DB, no way to improve on that.