MBP Running Hot & Slow

Yes, 40% idle is definitely a cause for concern. Please check the Apple article below for assistance with checking.

http://support.apple.com/kb/TS1473

Stedman

Disconnect all wired peripherals except keyboard, mouse, and monitor, if applicable. Launch the usual set of applications you use when you notice the slowdown.

Step 1

Launch the Activity Monitor application in any of the following ways:

☞ Enter the first few letters of its name into a Spotlight search. Select it in the results (it should be at the top.)

☞ In the Finder, press the key combination shift-command-U. The application is in the folder that opens.

☞ If you’re running Mac OS X 10.7 or later, open LaunchPad. Click Utilities, then Activity Monitor in the page that opens.

Select the CPU tab. Select All Processes from the popup menu in the toolbar, if not already selected. Click the heading of the % CPU column in the process table to sort the entries by CPU usage. You may have to click it twice to get the highest value at the top. What is it, and what is the process? Also post the values for % User, % System, and % Idle at the bottom of the window.

Now select the System Memory tab. What values are shown in the bottom part of the window for Page outs and Swap used?

Step 2

Launch the Console application in the same way as above, and select “kernel.log” from the file list. Post the dozen or so most recent messages in the log – the text, please, not a screenshot. If there are repeats, please post only one example of each repeated message.

Look at this thread, we all have the same problem.

https://discussions.apple.com/thread/2778179?start=0&tstart=0

https://discussions.apple.com/thread/3783313

ont of the room.

Hardware Test, a newer machine needs a Internet connection (don't move the machine after rebooting)

https://support.apple.com/kb/ht1509

Try installing a copy of Smart Utility http://www.volitans-software.com/smart_utility.php and check the condition of your HDD

It Shows the SMART data from the drive. you should see Verified, Failing or Failed when you run it

Your system is slow because of excessive swapping of data between physical memory and virtual memory.

That can happen for two reasons: (1) You have a long-running process with a memory leak (i.e., a bug), or (2) you don't have enough memory installed for your usage pattern.

Tracking down a memory leak can be difficult, and it may come down to a process of elimination. In Activity Monitor, click the heading of the Real Mem column in the process table once or twice to sort the table with the highest value at the top. Repeat with the Virtual Mem column. If one process (not including "kernel_task") is using much more memory than all the others, that could be an indication of a leak. A better indication would be a process that continually grabs more and more memory over time without ever releasing it.

In this case, it seems clear that Firefox or one of its plugins is at fault.

You've been given a suggestion to install a commercial diagnostic product. Before you spend money on that product, you should be aware of the following facts:

1. It's a GUI wrapper for the open-source command-line program "smartmontools," which is free.

2. There's no empirical evidence that monitoring the SMART data of a hard drive more closely than you can with Disk Utility helps to predict failure.

3. There's also no reason to think that your problem is caused by a drive malfunction.

Does your system run slow when you quit Firefox, or never launch it?