Wrong memory usage?

Hi!

On the server status page my “Memory usage” shows:

Available memory 11GB
Used memory 7GB

for my a 16GB server, which doesn’t make much sense (11GB+7GB = 18GB > 16GB). The memory state is read from /proc/meminfo and it seems the used memory is calculated this way:

used = MemTotal - MemFree - Buffers - Cached.

My question is: why is it calculated that way and not simply by:

used = MemTotal - MemAvailable

? In my case the latter would give a usage of ~4GB, which is also what commands “free -h“ and “htop“ show for the used memory.

My understanding is that cached and buffered memory are used by the OS to improve performance, but that memory is actually available for the applications if they need it. So your formula also makes sense. Yet somehow the result doesn’t match MemTotal - MemAvailable. I suspect there are other type of hidden caches not taken in account here.

Could you shed some light on this?

Great product by the way!

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