Dr. Mac's OS X Tip-of-the-Day  

I don't know about you but I'm always curious how RAM is used by the applications and processes I have running. In the old days we used to look at About this Macintosh for a detailed summary of which application was using how much RAM. OS X provides even more feedback about RAM usage (and virtual memory, CPU, and lots of other usages) but makes it more difficult to find and evaluate the information.

First I'll share the Process Viewer and Terminal ways, straight from the Apple Knowledgebase, then I'll talk about the easy $5 way.

How to View Memory Usage and Installed RAM Article ID: 106386

TOPIC

Use the About This Mac window and Process Viewer to check the amount of installed RAM (physical memory) and the amount of memory being used.

DISCUSSION

Viewing the amount of RAM (Physical Memory) installed

• 1 - Choose About This Mac from the Apple Menu.
• 2 - The Memory field specifies the amount of RAM installed in the computer.

Note: Mac OS X does not display the memory allocation and usage levels of individual applications in the About This Mac Window. Mac OS X automatically manages memory allocation and usage. This is different from earlier versions of Mac OS.

Viewing memory usage

• 1 - Open ProcessViewer (located at /Applications/Utilities/).
• 2 - Mac OS X processes and applications are listed in the Process Viewer window. The column on the right, "% Memory," indicates the percentage of RAM in use by an application or process at the time of sampling.
• 3 - Advanced users may use the Terminal to view memory usage. Please see document 106415: "Mac OS X 10.0: How to View Memory Usage With top" which appears below.

Notes

• 1 - It is normal for some processes to use very little RAM at times, such as 0.0% or 0.1%.
• 2 - It is normal for a process' memory usage to change dramatically from one sample period to another, depending on how you are using your computer.
• 3 - Not all application names in the Process Listing window are easily recognized. For example, Microsoft Internet Explorer 5.1 may appear as "LaunchCFMApp." This is normal.
• 4 - Classic applications do not appear individually in the Process Listing window. The Classic environment appears as a single process (TruBlueEnvironme). This is normal.
• 5 - ProcessViewer itself is listed because it is an open application. This is normal.

How to View Memory Usage With the "top" Utility Article ID: 106415

This article offers an advanced technique. You may perform similar monitoring with the ProcessViewer application. For information on using the ProcessViewer for this task, please see technical document 106386: "Mac OS X 10.0: How to View Memory Usage and Installed RAM" which appears above.

Viewing memory usage with top

• 1 - Open Terminal (located at /Applications/Utilities/).
• 2 - Type: top
• 3 - Press Return to open the top utility in the Terminal window. Two rows near the top of the window, "PhysMem:" and "VM:" indicate overall physical RAM and virtual memory usage, respectively. The two columns on the right, "RSIZE" and "VSIZE" offer memory usage information per application. RSIZE indicates the amount of physical RAM in use by the application or process, in megabytes ("M") or kilobytes ("K"). VSIZE indicates the amount of virtual memory Mac OS X has assigned for this process or application, in megabytes ("M") or gigabytes ("G").
• 4 - When you are finished reviewing the information, press the Q key to exit top.

Notes

• 1 - Application and process names are listed in the "COMMAND" column.
• 2 - It is normal for some processes to use very little RAM, such as 64K.
• 3 - Not all applications may have an easily-recognizable name in the Terminal window. For example: Microsoft Internet Explorer 5.1 appears as "Internet E."
• 4 - As with Process Viewer, Classic applications do not appear individually in the Process Listing window. It is normal for the Classic environment to appear as a single process (TruBlueEnv).
• 5 - top itself is listed because it is an open application. This is normal.
• 6 - Type "man top" in the Terminal for more information on top.

But the easiest way I've found is a little $5 shareware program called Memory Usage Getter 2.0.1 from Ellipsis Productions:

https://homepage.mac.com/simx/

Memory Usage Getter offers a display similar to the old About this Macintosh window, with bars showing memory use for Applications, User Processes, and System Processes, plus it tells you overall memory used, wired memory used, active memory used, and inactive memory used.

On the downside, it's a fairly large and unattractive window that refuses to stay where you put it, and it nags you for the $5 far too often and far too soon. Even so I was happy to send the developer $5 for it. He's a nice fellow and seems to fix "quirks" quickly. Give it a try.

To discuss this tip (or anything you like) in Dr. Mac's OSXFAQ Forum, click here:

https://forums.osxfaq.com/viewtopic.php?topic=564&forum;=100

Bob LeVitus is a leading authority on Mac OS and the author of 37 books, including Mac OS X For Dummies and The Little iTunes Book.