That’s a different mechanism. A “page” is just a fixed-size portion of memory, e.g. 4 KiB, which is a convenient size for your OS to do its whole memory management with. And then there’s many things the OS does with such pages.
Page caching keeps files that processes loaded from your hard drive in RAM, after the process doesn’t need it anymore.
What you’re referring to is kind of the opposite. The OS allows processes to reserve more memory than there is physically available. This is called “virtual memory”.
When processes do that, then some of those portions of memory pages get put onto your hard drive, and only get put back into RAM (replacing something else) when the process actually accesses those pages.
The fundamental result isn’t much different, there’s 30 GB of populated memory being sent to disk because these apps all over allocate and the os insists on sending it to disk even with 40% of real ram free.
That’s a different mechanism. A “page” is just a fixed-size portion of memory, e.g. 4 KiB, which is a convenient size for your OS to do its whole memory management with. And then there’s many things the OS does with such pages.
Page caching keeps files that processes loaded from your hard drive in RAM, after the process doesn’t need it anymore.
What you’re referring to is kind of the opposite. The OS allows processes to reserve more memory than there is physically available. This is called “virtual memory”.
When processes do that, then some of those
portions of memorypages get put onto your hard drive, and only get put back into RAM (replacing something else) when the process actually accesses those pages.The fundamental result isn’t much different, there’s 30 GB of populated memory being sent to disk because these apps all over allocate and the os insists on sending it to disk even with 40% of real ram free.