Percentage of total memory utilization is shown above 100%.

[Ramon Ar]

hi, my english is not good, but i´m gonna try..

in linux, Kernell uses all available physical memory cache to maximize the use of RAM, and so expedite the process. In this case you always see 90 or 99% of RAM used



total used free buffers cached

Mem: 16055 4264 11790 15 3027
-/+ b/cache 1221 14833
Swap: 8189 0 8189

as you can see, the amount of free memory and buffer cache is equal to the free virtual memory, if you make a drop_caches in RH or CentOS, you can watch free virtual memory to continue with the same value, in this case 14 833

free -m|awk '{print $3}'|tail -2|head -1 this is de used memory

[Steven E. Protter]

Shalom,

Memory use can be over 100%, depending on the definition of memory.

If you define memory as RAM, and you have programs of services running in excess of that total, inactive processes will be swapped to disk. Memory use will exceed RAM.

If you define memory as ram plus swap, than it is not possible to exceed 100% memory utilization.

I believe the statement on server 2 is a situation defined above, where memory is being calculated based on physical memory, not total capacity.

What does vmstat show on server 2?

SEP

[Ramon Ar]

something like that, if we take just as RAM memory, not swap, ie, the idea is to know what the amount of RAM actually used, I think that if we define it that way, the amount of cache + buffer + Free RAM, we could determine an approximate amount of actual free RAM

[Balasubramanian, Raja]

HI Senthil,
I understand your requirement, in a simple manner the solution to your query would be to use free -m
For eg:
$ free -m
total used free shared buffers cached
Mem: 32186 18596 13590 0 828 13587
-/+ buffers/cache: 4180 28006
Swap: 16386 0 16386

From the above o/p the amount of memory actually in use is 4180( free command takes care of calculating the buffers and cache). From this, you can arrive at the percentage usage of memory on your linux server ( In this case would be ~13% used)

Thanks,
RB