• Home
  • About
    • Stephen Foskett
      • My Publications
        • Urban Forms in Suburbia: The Rise of the Edge City
      • Storage Magazine Columns
      • Whitepapers
      • Multimedia
      • Speaking Engagements
    • Services
    • Disclosures
  • Categories
    • Apple
    • Ask a Pack Rat
    • Computer History
    • Deals
    • Enterprise storage
    • Events
    • Personal
    • Photography
    • Terabyte home
    • Virtual Storage
  • Guides
    • The iPhone Exchange ActiveSync Guide
      • The iPhone Exchange ActiveSync Troubleshooting Guide
    • The iPad Exchange ActiveSync Guide
      • iPad Exchange ActiveSync Troubleshooting Guide
    • Toolbox
      • Power Over Ethernet Calculator
      • EMC Symmetrix WWN Calculator
      • EMC Symmetrix TimeFinder DOS Batch File
    • Linux Logical Volume Manager Walkthrough
  • Calendar

Stephen Foskett, Pack Rat

Understanding the accumulation of data

You are here: Home / Everything / Apple / How To Tell If Your Mac Needs More Memory

How To Tell If Your Mac Needs More Memory

December 13, 2012 By Stephen 1 Comment

It’s not always easy to tell if your system needs more memory, or if it’s just slow. In this article, I will present an easy method for even a computer novice to know whether he has enough memory on his Mac!

Virtual Memory and Page Outs

Most people are aware that computers contain at least two different kinds of memory:

  1. Main system RAM is used by running programs
  2. Disks are used for long-term storage

But the lines blur in reality, with modern operating systems able to use disk storage for running applications. Although using disk as memory (a process called paging or virtual memory swapping) allows your system to have effectively infinite RAM, it often slows down performance to an unacceptable level.

Is your system constrained with two little memory, or is it just slow? It can be difficult for the uninitiated to answer this question, but it’s not too difficult to see if your system is swapping excessively: most operating systems will tell you how many “page outs” the system has needed to do, and this is a very strong clue as to whether you have enough memory or not.

Check Activity Monitor in Mac OS X

On Mac OS X, the easiest way to see if you have enough memory is simply to open the Activity Monitor application. You will find this under Applications in the Utilities folder, and it shows you all Certs of useful information about CPU, memory, disk, and network activity.

In Activity Monitor, click on the System Memory tab. At the bottom, next to the pie chart of memory in use, you will see a “Page outs” value. This is the clue you need to know if your system has insufficient memory.

If you have many GB of "Page outs", you should consider getting more RAM!
If you have many GB of “Page outs”, you should consider getting more RAM!

“Page outs” in Activity Monitor shows how much memory has been needed but not available since your system last started up. Since it is much slower than RAM, disk space should be thought of as “overdraft protection” for your system memory. It’s fine to dip into it occasionally, but excessive use will cause trouble!

Reboot, run your system normally for a few days, then check Activity Monitor. There is no hard and fast rule, but if the number is higher than a gigabyte or two over a few days use you ought to consider getting more memory!

What About SSDs?

Fast solid-state storage (SSD) drives reduce the impact of page outs. This is one reason that the meager 2 GB or 4 GB of RAM found in a MacBook Air doesn’t impact performance as much as one would think. This begs the question if SSD-equipped computers need as much system RAM.

Even though SSDs are much faster than hard drives, they are slower than main system memory. And SSDs don’t last forever, so excessive page-outs actually reduce the lifespan of your computer. These are true statements, but should be taken with a grain of salt. After all, a computer only needs to be “fast enough” for the user to be satisfied, and the lifespan of the SSD is probably not as much concern as lifespan of the battery!

It is wise to buy enough system RAM to handle your needs, even if your computer uses an SSD. But it is not as much of a necessity, so don’t fret if you can only buy 4 GB. Personally, I was willing to spend the extra money for 16 GB in my retina MacBook Pro, even though it uses one of the fastest SSDs on the market. But I would have happily bought it with 8 GB if that was not an option, and it will perform great either way.

Stephen’s Stance

In this day of soldered-in system RAM and SSDs, it is difficult to decide what to buy. I recommend checking the page outs on your computer to see how much RAM you really need, then deciding whether to upgrade or buy a new computer with more RAM, especially if you’re using a hard disk drive for storage!

You might also want to read these other posts...

  • Plexistor Integrates NVDIMM for Every Application
  • Diablo Memory 1 Takes Memory Channel Flash To The Next Level
  • Download My Free E-Book, “Essential Enterprise…
  • Infinidat’s Solution For the I/O Blender: Math
  • Apple Packs PCIe SSD Alongside PC-Fast CPU and…

Filed Under: Apple, Ask a Pack Rat, Terabyte home Tagged With: Activity Monitor, Mac OS X, MacBook Air, MacBook Pro, Paging, RAM, SSD, Virtual Memory

Technology is the name we give to things that don’t work yet

Danny Hillis

Subscribe via Email

Subscribe via email and you will receive my latest blog posts in your inbox. No ads or spam, just the same great content you find on my site!
 New posts (daily)
 Where's Stephen? (weekly)

Download My Book


Download my free e-book:
Essential Enterprise Storage Concepts!

Recent Posts

Add a Mirror to an Existing ZFS Drive

December 11, 2017

How To Remove Raw Images From Apple Photos and iCloud

How To Remove Raw Images From Apple Photos and iCloud

July 24, 2017

Recalling An HP MediaSmart Server To Active Duty

Recalling An HP MediaSmart Server To Active Duty

July 21, 2017

Go Get a ProtonMail Account and Protect Your Online Life!

Go Get a ProtonMail Account and Protect Your Online Life!

July 19, 2017

ZFS Is the Best Filesystem (For Now…)

ZFS Is the Best Filesystem (For Now…)

July 10, 2017

Co-Processors, GPGPU, and Heterogeneous Computing

Co-Processors, GPGPU, and Heterogeneous Computing

June 26, 2017

What is OCuLink?

What is OCuLink?

June 22, 2017

Storage is Getting Cloudier!

Storage is Getting Cloudier!

June 21, 2017

Where Have All The GPU’s Gone? Cryptocurrency Mining!

Where Have All The GPU’s Gone? Cryptocurrency Mining!

June 11, 2017

Turn Off Error Recovery in RAID Drives: TLER, ERC, and CCTL

Turn Off Error Recovery in RAID Drives: TLER, ERC, and CCTL

May 30, 2017

Symbolic Links

  • Cisco’s Latest AP is Mind-Blowing (and a quick history lesson)

  • E8 Storage Announces InfiniBand Support

  • Wireless Controller Extinction?

  • Using GnuCash as a Freelancer to Track Finances and Prepare Taxes

  • Do We Need Regulations For IoT Security?

Featured Posts

The Best Mac OS X Terminal Font: Glass TTY VT220

October 6, 2015

Free as in Coffee – Thoughts on the State of OpenStack

May 2, 2016

Follow the Yellow Brick Road to the Software-Defined Future

November 29, 2012

Why You Should Never Again Utter The Word, “CIFS”

February 16, 2012

The Fat Middle: Today’s Enterprise Storage Array

August 31, 2014

How Will Cisco Recover From The Consumer Strategy Blunder?

January 2, 2013

Deduplication Coming to Primary Storage

September 16, 2008

10 Mysteries The Lost Finale Definitively Settled

May 25, 2010

How To Sync Your iPad With Your Exchange Server

April 3, 2010

The Four Horsemen of Storage System Performance: The Rule of Spindles

August 25, 2010

Copyright © 2018 · Log in