# pidstat(1) Trace minor/major page faults. ```markdown pidstat -r -p [interval] minor_pagefault: happens when the page needed is already in memory but not allocated to the faulting process, in that case the kernel only has to create a new page-table entry pointing to the shared physical page major_pagefault: happends when the page needed is NOT in memory, the kernel has to create a new page-table entry and populate the physical page ```