> how much time did I spend waiting to swap-in a page You can do this with eBPF/BCC by using funclatency (https://github.com/iovisor/bcc/blob/master/tools/func

> how much time did I spend waiting to swap-in a page You can do this with eBPF/BCC by using funclatency (https://github.com/iovisor/bcc/blob/master/tools/funclatency.py https://github.com/iovisor/bcc/blob/master/tools/funclatency...) to trace swap related kernel calls. It depends on exactly what you want, but take a look at mm/swap.c and you'll probably find a function which results in the semantics you want.