I would like to thank everyone who has contributed to this thread. It is immensely useful to someone like me who is the equivalent of tone deaf to technical aspects of computing . It is saved for reference along with all such general information provided by you generous people.
regards, Jennifer On 21 February 2011 08:20, Peter Hinchliffe <hinch...@multiline.com.au>wrote: > > On 18/02/2011, at 12:50 PM, Ronda Brown wrote: > > Hi David, > > > *Activity Monitor Pie Chart* > > The Activity Monitor pie chart shows four types of memory usage: Free > (green), Wired (red), Active (yellow), and Inactive (blue). > In order to understand your memory usage, you need to know what each memory > type is and how it affects available memory. > > <http://macs.about.com/od/usingyourmac/qt/os-x-memory-usage.htm> > > When you launch a program, it gets loaded into active memory. When you quit > a program, however, it doesn't get removed from RAM; rather, it gets bumped > into inactive memory. This is why it is often faster to re-launch a program > -- it is still in RAM (try this with a Application like Firefox). > > Once all your memory is used (free memory is 0), the OS will write out > inactive memory to the swapfile to make more room in active memory. > > If a program gets paged out to the swapfile, and you re-launch it, it'll > get pulled from the swapfile into active memory. > > So in short, you actually shouldn't care if your free memory is low. In > fact, you want it to be low -- free memory is wasted memory (as the OS isn't > using it for anything). > > When examining how much memory your computer is using, you actually want to > pay attention mostly to Swap used, which tells you the size of the > virtual memory swapfile, and Page ins, which tells you how often the OS has > to pull memory from the swapfile into active memory. > > > To explain how OS X uses memory would ‘fill a book’. A good start is Mac OS > X Reference Library: Memory Usage Performance Guidelines. > < > http://developer.apple.com/library/mac/#documentation/Performance/Conceptual/ManagingMemory/ManagingMemory.html%23//apple_ref/doc/uid/10000160-SW1 > > > > < > http://developer.apple.com/library/mac/#documentation/Performance/Conceptual/ManagingMemory/Articles/AboutMemory.html > > > > Hope this is of benefit to you David. > > Cheers, > Ronni > > > Just to follow up Ronni's customary excellent advice, I would like to take > the opportunity to recommend the excellent resource called iStat Menus ( > http://bjango.com/mac/). I should add the caveat that I recommend it for > users who are able to take advantage of a nice,wide monitor, eg, 24" iMac or > greater. Users of Macbook Pro 15" or smaller are better off with iStat Pro > (or its new replacement MiStat), both from the same company. iStat Menus > places a number of icons in your Menu Bar at the top of the screen (which is > why you need lots of room to see them) which give you constant visual > feedback about the state of your computer's use of such things as RAM usage, > CPU performance, network traffic and hard drive use. The program is highly > configurable, so it's completely up to you just what items you want > displayed. I find it invaluable when it comes to what is causing my Mac to > slow down, and can tell at a glance whether problem has to do with CPU > overload, RAM issues or a choked internet connection, and I can take > suitable action without having to spend a lot of time guessing the problem. > iStat Menus is not free, but it's worth every penny. > > The Bjango website has some excellent general articles as well. > > Peter Hinchliffe Apwin Computer Services > FileMaker Pro Solutions Developer > Perth, Western Australia > Phone (618) 9332 6482 Mob 0403 046 948 > -------------------------------------------------------------------- > Mac because I prefer it -- Windows because I have to. > > > > ------------------------------ > > -- The WA Macintosh User Group Mailing List -- > Archives - <http://www.wamug.org.au/mailinglist/archives.shtml> > Guidelines - <http://www.wamug.org.au/mailinglist/guidelines.shtml> > Unsubscribe - <mailto:wamug-unsubscr...@wamug.org.au> > -- The WA Macintosh User Group Mailing List -- Archives - <http://www.wamug.org.au/mailinglist/archives.shtml> Guidelines - <http://www.wamug.org.au/mailinglist/guidelines.shtml> Unsubscribe - <mailto:wamug-unsubscr...@wamug.org.au>
