Ram usage go insane

I have a 6GB of RAM with no paging file. For a long time it was OK but lately, the RAM started to go crazy.

I mostly have Firefox open and lately I have eclipse. The memory in performance tab is always much more than the total memory of the processes memory. When I open the computer, it looks OK but as time goes by, the RAM accumulates. When that happens and I close everything, the memory is around 3GB as if something hangs on it and won't let go no matter what. Ofcourse, if I reopen Firefox and eclipse, soon enough, the memory goes back closer to 5.5GB and the memory problems reappear.

I have no idea what is it as in the processes tab, I see no abnormal memory usage it's as if something external is holding this memory and won't let go. I attached a screenshot of RAMMAP - do you see anything suspicious?

Thanks!

Adding RAM won't help as it will just postpone the time for the problem to occur, 6GB seems more than fair for my needs.

I already closed everything I don't need and even then, the RAM is around 3.5GB so when re-opening Firefox and Eclipse, which I use often, the memory goes up to 4.5-5.5 and from there to the RAM disaster, the path is short.

There are 2 things that seem odd. First, the modified memory is very high. Without a pagefile this is going to be high but this is rather to much. There seems to be a memory leak but the cause is unknowable from the display. Second, the free memory is disturbingly high. In itself that is not too unusual but combined with the high modified memory it is disturbing. The only possibilities I can see are that a large program was recently closed or you are running one of those memory "optimizers". I hope it is not the latter.

I would like to see a screenshot of Task Manager, Performance tab. This gives an overview of the memory situation not seen anywhere else. With memory problems that is where I like to start. A screenshot of Resource monitor showing the memory tab and the list sorted by commit would also be useful.

The total of the values in the memory usage column in Task manager will never equal total usage. Memory management in any modern OS is far too complex for anything that simple. Among other things there are major users of memory that are not processes.

Thank you all for your replies. When I left my computer, it was on 4.3GB with no popup messages, when I returned to it, several hours afterwards, it was on 4.6GB and the popup message to close the highest memory consumption application was shown. Even now, I'm on 4.6GB and I got another popup saying my computer is low on memory in general, but I should have 1.4GB free! so why is it considered low?

Here is a screenshot of my specs + performance tab, do you need any other info?

I did try to use 1 memory optimizer but nothing happened so I removed it, nothing like that is running in the background though, it was a one time try (and fail). the 2 applications I have are Firefox (700mb) and java/emulator (mobile device) which are up to 800-900mb. It could be that rammap snapshot was taken after closing and reopening the 2 applications as part of me trying to understand what happens.

Will you recommend me to use a pagefile? I removed that long time ago and didn't have a problem, not sure what happened suddenly

Is there a real working ram cleaner application out there? I can't consider a reboot once a day as a solution :)

My computer just died so I had to restart... I hope the processes tab is not that significant.

Now Firefox + java + emulator are open and the performance is on 2.97GB, let's see what happens next. I hope the info I posted will suffice.