Top command cache vs free memory












2















When I am running top command (on embedded system with 64 MB RAM) I am getting below description on total memory usage:



"Mem: 43468K used, 968K free, 0K shrd, 1280K buff, 21896K cached"



It looks like I have only 968 KB of ram free. But meanwhile I can see 21896KB in cache. Can I allocate (malloc) more than 968 from an application meantime ? If I do so, will the ram be reclaimed from cache ?










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    2















    When I am running top command (on embedded system with 64 MB RAM) I am getting below description on total memory usage:



    "Mem: 43468K used, 968K free, 0K shrd, 1280K buff, 21896K cached"



    It looks like I have only 968 KB of ram free. But meanwhile I can see 21896KB in cache. Can I allocate (malloc) more than 968 from an application meantime ? If I do so, will the ram be reclaimed from cache ?










    share|improve this question

























      2












      2








      2








      When I am running top command (on embedded system with 64 MB RAM) I am getting below description on total memory usage:



      "Mem: 43468K used, 968K free, 0K shrd, 1280K buff, 21896K cached"



      It looks like I have only 968 KB of ram free. But meanwhile I can see 21896KB in cache. Can I allocate (malloc) more than 968 from an application meantime ? If I do so, will the ram be reclaimed from cache ?










      share|improve this question














      When I am running top command (on embedded system with 64 MB RAM) I am getting below description on total memory usage:



      "Mem: 43468K used, 968K free, 0K shrd, 1280K buff, 21896K cached"



      It looks like I have only 968 KB of ram free. But meanwhile I can see 21896KB in cache. Can I allocate (malloc) more than 968 from an application meantime ? If I do so, will the ram be reclaimed from cache ?







      linux memory virtual-memory top






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      asked May 3 '13 at 10:36









      Lunar MushroomsLunar Mushrooms

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          Linux will use available memory for disk caching, unless it's required by a running program.
          So your you can allocate (used - cached + free) amount of memory, in your case, 43468 - 21896 + 968






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            Linux will use available memory for disk caching, unless it's required by a running program.
            So your you can allocate (used - cached + free) amount of memory, in your case, 43468 - 21896 + 968






            share|improve this answer




























              0














              Linux will use available memory for disk caching, unless it's required by a running program.
              So your you can allocate (used - cached + free) amount of memory, in your case, 43468 - 21896 + 968






              share|improve this answer


























                0












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                0







                Linux will use available memory for disk caching, unless it's required by a running program.
                So your you can allocate (used - cached + free) amount of memory, in your case, 43468 - 21896 + 968






                share|improve this answer













                Linux will use available memory for disk caching, unless it's required by a running program.
                So your you can allocate (used - cached + free) amount of memory, in your case, 43468 - 21896 + 968







                share|improve this answer












                share|improve this answer



                share|improve this answer










                answered Jun 22 '14 at 18:26









                Tuo LeiTuo Lei

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