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I'm investigating a server used for scientific data analysis. It's running RHEL 6.4 It has almost 200GB of RAM. It's been running very slowly for users via SSH, and after some poking around I quickly noticed that the RAM usage was sky-high. What's odd is that even in an idle state it's still using a ton of RAM:
I also looked via
htop and I can't see that any running process is using more than 0.1% of the RAM. So I wonder what's going on? Right now the only user-initiated process running is an rsync between two NFS-mounted shares.
I tried rebooting the server and it was much more responsive for a few minutes, but then memory usage shot up again.
Is there any way I can pinpoint why memory usage is so high?