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Nynte

macrumors newbie
Original poster
Aug 28, 2009
16
0
Hey,

I'm noticing a strange thing in Activity Monitor, where the total used RAM is much higher than the sum of the RAM used by all running processes. It became much more noticeable after I upgraded my RAM to 12GB from 4, and after using the Mac for a while.

For example, the sum of the RAM used (Based on whatever appeared in Real Mem under Activity Monitor) by all processes in the system was about 2.87GB; yet the Activity Monitor's total showed:
Code:
Active Memory:		7.03	GB
Free Memory:		2.4	GB
Wired Memory:		905.9	MB
Used Memory:		9.59	GB
Inactive Memory:	1.67	GB

Could anyone explain why and how this happens and how do I fix it? It's almost 7GBs of RAM I'm missing.

Thanks! :)
 

GGJstudios

macrumors Westmere
May 16, 2008
44,545
943
Hey,

I'm noticing a strange thing in Activity Monitor, where the total used RAM is much higher than the sum of the RAM used by all running processes. It became much more noticeable after I upgraded my RAM to 12GB from 4, and after using the Mac for a while.

For example, the sum of the RAM used (Based on whatever appeared in Real Mem under Activity Monitor) by all processes in the system was about 2.87GB; yet the Activity Monitor's total showed:
Code:
Active Memory:		7.03	GB
Free Memory:		2.4	GB
Wired Memory:		905.9	MB
Used Memory:		9.59	GB
Inactive Memory:	1.67	GB

Could anyone explain why and how this happens and how do I fix it? It's almost 7GBs of RAM I'm missing.

Thanks! :)

This may help you to understand the readings:

Using Activity Monitor to read System Memory and determine how much RAM is being used
 

Nynte

macrumors newbie
Original poster
Aug 28, 2009
16
0
I've read that article before, it still doesn't explain this mismatch. Even if I cut the inactive memory from the sum, it would be almost 8GB of RAM being used. However, the sum of the RAM used by all open processes is 2.87GB. What is using the remaining 5GB of RAM?
 

Guiyon

macrumors 6502a
Mar 19, 2008
771
4
Cambridge, MA
I would assume that it's probably being used for caching. OS X tends to leave things in memory as long as possible; free RAM is wasted RAM.

Edit: Misread the 'Active Memory' section. That is kind of odd. Are you viewing all processes from all users in the Activity Monitor or just your own?
 

benwiggy

macrumors 68020
Jun 15, 2012
2,382
199
Code:
Active Memory:		7.03	GB
Free Memory:		2.4	GB
Wired Memory:		905.9	MB
Used Memory:		9.59	GB
Inactive Memory:	1.67	GB
You have 12 Gb, yes?
7Gb Active, + ~1Gb Wired, + 1.67Gb Inactive = Used (9.59)
Used + Free = 12Gb.
 

Nynte

macrumors newbie
Original poster
Aug 28, 2009
16
0
You have 12 Gb, yes?
7Gb Active, + ~1Gb Wired, + 1.67Gb Inactive = Used (9.59)
Used + Free = 12Gb.

That's not the issue. The issue is that if I sum the RAM used per process, the actual amount of used memory, excluding inactive memory, is 2.8GB, which is far less than the 8GB Activity Monitor reports.

@Guiyon: Yes, Activity Monitor is configured to show all processes. Isn't the cache simply the Inactive Memory?
 

benwiggy

macrumors 68020
Jun 15, 2012
2,382
199
Without seeing the complete output from Activity Monitor (or top in the Terminal), it's not going to be easy to say anything about this.
 

Nynte

macrumors newbie
Original poster
Aug 28, 2009
16
0
Here's the memory usage from the time this happened, as exported by Activity Monitor:
Code:
Active Memory: 7.03 GB
Free Memory: 2.40 GB
Wired Memory: 905.9 MB
Used Memory: 9.59 GB
Inactive Memory: 1.67 GB
Total VM: 278.07 GB
Number of processes: 115

PID    Process Name              Real Mem        
0      kernel_task               776.2 MB        
1      launchd                   1.8 MB          
10     kextd                     4.6 MB          
11     UserEventAgent            6.6 MB          
12     mDNSResponder             3.5 MB          
13     opendirectoryd            9.6 MB          
14     notifyd                   1.3 MB          
15     diskarbitrationd          1.6 MB          
16     configd                   5.4 MB          
17     fseventsd                 7.0 MB          
18     syslogd                   1.1 MB          
20     powerd                    2.1 MB          
21     distnoted                 1.9 MB          
22     blued                     4.3 MB          
25     securityd                 8.0 MB          
27     coreservicesd             71.4 MB         
55     ntpd                      1.4 MB          
56     named                     7.5 MB          
58     cron                      832 KB          
60     warmd                     4.7 MB          
63     SystemStarter             1.1 MB          
65     stackshot                 1.2 MB          
68     revisiond                 5.6 MB          
69     ptmd                      1.7 MB          
72     netbiosd                  4.6 MB          
73     mds                       105.3 MB        
75     loginwindow               53.1 MB         
77     KernelEventAgent          1.0 MB          
78     kdc                       2.9 MB          
80     hidd                      2.0 MB          
82     dynamic_pager             756 KB          
84     dpd                       1.8 MB          
89     autofsd                   1.8 MB          
91     applepushserviced         7.1 MB          
92     aosnotifyd                4.8 MB          
113    WindowServer              160.3 MB        
117    httpd                     7.8 MB          
123    httpd                     2.7 MB          
124    CVMServer                 1.1 MB          
136    logind                    1.8 MB          
138    coreaudiod                5.5 MB          
152    cma                       10.0 MB         
153    launchd                   1.5 MB          
156    UserEventAgent            8.4 MB          
158    distnoted                 5.4 MB          
163    Dock                      46.6 MB         
164    talagent                  14.8 MB         
165    SystemUIServer            33.1 MB         
171    pboard                    952 KB          
173    fontd                     23.9 MB         
181    com.apple.dock.extra      15.1 MB         
183    lsboxd                    8.2 MB          
185    imagent                   6.5 MB          
192    warmd_agent               1.8 MB          
204    MagicPrefs                19.4 MB         
211    TISwitcher                11.7 MB         
212    GrowlHelperApp            18.5 MB         
213    Caffeine                  8.8 MB          
219    Mail                      101.8 MB        
220    VMware Fusion Start Menu  11.1 MB         
223    syspolicyd                6.3 MB          
234    AppleSpell.service        12.9 MB         
268    launchd                   880 KB          
288    Activity Monitor          31.7 MB         
290    activitymonitord          6.7 MB          
375    filecoordinationd         8.4 MB          
556    httpd                     1.7 MB          
557    httpd                     1.7 MB          
559    httpd                     1.7 MB          
560    httpd                     1.7 MB          
561    httpd                     1.7 MB          
562    httpd                     1.7 MB          
563    httpd                     892 KB          
564    httpd                     692 KB          
1523   Nozbe                     74.0 MB         
4879   Calculator                14.1 MB         
6383   DashboardClient           24.6 MB         
6530   Adium                     60.8 MB         
14686  mdworker                  36.4 MB         
14689  mdworker                  9.3 MB          
14690  distnoted                 1.3 MB          
15100  MagicPrefsPlugins         17.6 MB         
19376  FontLab Studio            56.2 MB         
20248  Finder                    64.6 MB         
20287  VMware Fusion             101.6 MB        
20350  VMware Fusion Services    868 KB          
20397  vmnet-bridge              2.7 MB          
20400  vmnet-netifup             192 KB          
20402  vmnet-dhcpd               216 KB          
20405  vmnet-natd                1.5 MB          
20408  vmnet-netifup             192 KB          
20410  vmnet-dhcpd               440 KB          
20412  vmware-usbarbitrator      2.1 MB          
25461  usbmuxd                   2.6 MB          
25467  Terminal                  30.6 MB         
25469  login                     2.2 MB          
25470  bash                      1.1 MB          
25476  appleprofilepolicyd       728 KB          
25542  iFreeMem                  11.7 MB         
25691  Google Chrome             151.4 MB        
25694  Image Capture Extension   8.7 MB          
25696  Google Chrome Worker      68.8 MB         
25697  Google Chrome Worker      28.3 MB         
25698  Google Chrome Worker      27.9 MB         
25699  Google Chrome Worker      27.8 MB         
25700  CIJScannerRegister        6.0 MB          
25703                            46.1 MB         
25704                            44.9 MB         
25705                            56.1 MB         
25706  ocspd                     2.4 MB          
25707                            44.9 MB         
25712                            43.4 MB         
25713                            48.1 MB         
25719                            123.4 MB        
25924  automountd                2.2 MB
(I'm not sure why a few of the last processes have no names.)
 
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