Hi Steven, You 'might' have some sort of memory leak; but Insufficient RAM and Free Hard Space do cause the problems you are experiencing. I'll try to type a fairly short response to your queries. I did post a long time back to WAMUG explaining 'Real Memory' & 'Virtual Memory' in OS X.
I always max out the RAM in my MBPs, 8GB RAM runs Lion fast, plus I also like to keep my Hard Drive with 30% free. Lion handles memory very well, but it does need free space to swap the contents of real memory to and from the drive. When your Mac gets low on real memory, virtual memory comes to the rescue. * Virtual memory means the system swaps the contents of real memory to and from the drive; this involves both writing (paging out), and reading (paging in). Virtual memory is far slower than real memory, so a fast system drive is the dominant factor for virtual memory performance. > I see that "Page outs" is defined as "number of virtual memory page > ins/outs", but the figure provided is, right now, 1.9MB. Isn't 1.9MB a volume > figure, as opposed to a "number of times" figure? I don't get it what 1.9MB > actually means in terms of "number of times". 'Page ins' or 'page outs' are how many times a page of memory is swapped out from disk to memory and vice versa. If the total 'page outs' is low compared to the number of 'page ins' after having used your Mac for hours of work, you may have sufficient RAM --- Otherwise, you should install more RAM. A few megabytes or tens of megabytes of 'page outs' are acceptable, but more than a few hundred megabytes means you’re losing performance in a major way— add more memory if possible. In my 'simple words' : This number indicates how many times your Mac has run out of available memory and used your hard drive as virtual RAM. This number should be as low as possible. I like the number to be less than 2000 during a full day's use of my Mac. Others suggest a higher value as the threshold for adding RAM, in the neighborhood of 2500 to 3000. *Always install more memory if possible, nothing else is faster than real memory. Cheers, Ronni 17" MacBook Pro 2.3GHz Quad-Core i7 “Thunderbolt" 2.3GHz / 8GB / 750GB @ 7200rpm HD OS X 10.7.3 Lion Windows 7 Ultimate (under sufferance) On 12/05/2012, at 8:04 AM, Steven Knowles wrote: > Thanks Ronni. > >> Have you checked your RAM usage in Activity Monitor? > > > There's always been adequate RAM for my use, other than the odd occasion when > more would be nice, which no doubt most people run into now and again. I > don't think I've ever bought a Mac without immediately doubling the RAM, > because unless you're the lightest of users, I think the default RAM > installations are inadequate (probably by design). But those peaking RAM > situations are usually temporary matters, solved by quitting another RAM > hungry application or two. > > My problem is this kind of gradual deterioration of performance and hard disk > capacity over a couple of days, which remains unresolved by quitting > processes. The only solution I've found so far is a restart, which apart from > it not having always been that way and shouldn't be, is a pain. > > >> Use Activity Monitor to watch your RAM usage. If Free memory falls to the >> point where Inactive memory is being released, you may want to consider >> adding more RAM to maintain maximum performance. > > > I'll keep my eye on that out of interest. Free RAM currently at 740MB, > inactive at 565MB. I'm reluctant to throw more RAM at it if the underlying > problem isn't solved. > > >> You can also look at the 'Page outs' value, at the bottom of Activity >> Monitor's main window. This number indicates how many times your Mac has >> run out of available memory and used your hard drive as virtual RAM. This >> number should be as low as possible. > > > I see that "Page outs" is defined as "number of virtual memory page > ins/outs", but the figure provided is, right now, 1.9MB. Isn't 1.9MB a volume > figure, as opposed to a "number of times" figure? I don't get it what 1.9MB > actually means in terms of "number of times". > > Cheers, Steven > > On 12/05/2012, at 9:11 AM, Ronda Brown wrote: > >> Hi Steven, >> >> Have you checked your RAM usage in Activity Monitor? >> Use Activity Monitor to watch your RAM usage. If Free memory falls to the >> point where Inactive memory is being released, you may want to consider >> adding more RAM to maintain maximum performance. >> >> You can also look at the 'Page outs' value, at the bottom of Activity >> Monitor's main window. This number indicates how many times your Mac has >> run out of available memory and used your hard drive as virtual RAM. This >> number should be as low as possible. >> >> Cheers, >> Ronni >> Sent from Ronni's iPad >> >> On 12/05/2012, at 3:38 AM, Steven Knowles <emai...@knowles.net.au> wrote: >> >>> I'm running 10.7.3 on a 17" MBP which is probably getting a bit aged these >>> days, 2.4 GHz Intel Core Due, 4 GB 667 MHz DDR2 SDRAM. >>> >>> At startup, I have around 50GB of spare hard disk capacity, of a total >>> 250GB disk. >>> >>> Over the past month o so, what happens is that over around a 2 to 4 day >>> period, the machine gets slower and slower, to the point that it's >>> unbearably slow, so a restart becomes necessary. >>> >>> In line with the progression of slowness, seems to be disappearance of hard >>> disk capacity. By the time I have to restart, a quick check of hard disk >>> capacity, and it's down to around 1 or 2GB. >>> >>> Trash is emptied regularly (I almost always use Secure Empty Trash). >>> >>> Any clues as to what might be causing this? >>> >>> I've just noticed 10.7.4 is out, so I'll update to that to see if that >>> makes a difference, but any hints in the meantime would be appreciated. >>> >>> Cheers, Steven -- 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> Settings & Unsubscribe - <http://lists.wamug.org.au/listinfo/wamug.org.au-wamug>
