http://www.perlmonks.org?node_id=297202


in reply to Re: Node cache refactoring (DBI profiling)
in thread Node cache refactoring

I just had an idea: We should have a nodelet (allowed for all -- that is, in sidebar nodelets or the allowed-to-all section of allowed nodelets) that gives the current web & db server load (probably cached), and, perhaps more importantly, how much db load this page caused. (Being a nodelet means that it will miss load caused by later nodelets, but I think that's better then putting it at the very bottom, where it's too easy to not notice.)

The best way to do this would seem to be adding $NODE->{node_id} (the node id of the node being rendered) and $USER->{title} (the username of the logged-in user) (possibly also a unique id for the HTTP request, but I'm not sure how to generate that -- mod_perl, as opposed to CGI, thing, thing).

Then the nodelet would have to sum up the information by parsing the logfile.

Come to think of that, that last step is probably rather difficult. A better way may be for the loging methods to also add information to $HTMLVARS (a global hashref, which is reloaded with every request).

In fact, we could also add logic to add daily totals to $VARS (user settings), which show how much total DB load you have caused today. That may be too much overhead for the logging methods, though -- they'd have to check if the day has changed every time. Also, that would mean yet more data in each fetch and store of the user, which is generaly a bad thing.

If you want, I can start working up code.


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