Quote:
Originally Posted by
tmonk1
We had 27GB free memory when restarted the server,But it continuously decreased to reach 1500M and keeping the free mem between 1500 to 3000.
I am no Solaris expert, but this is a common trait of UNIX-kernels: they commit otherwise unused memory to file caching. When you start there is a lot of free RAM as no applications have been started yet but at the same time there is nothing which makes sense to cache, so the RAM remains free.
Once your application(s) start(s) not only does that use RAM but the processes also use (-> load/write to) certain parts of the filesystem to work with. Now that a pattern of file usage emerges the UNIX kernel uses leftover RAM to cache exactly these parts of the filesystem. Hence the free memory seemingly drops.
Most UNIX kernels (and i suppsoe Solaris does too, in AIX this is called minperm and maxperm) also have some tuning parameter for how much memory should not be used for file caching but always be available for programs. I suppose this is set to effectively 1.5GB, so you see the memory not dropping below this point.
I hope this helps.
bakunin