[yocto] sstate-cache hit/miss

[Trevor Woerner]

Is there a simple way to determine how well (or not) the sstate-cache
is being hit during a build?

At the end of a build there is always that line saying (something
along the lines of):

    NOTE: Tasks Summary: Attempted X tasks of which Y didn't need to
be rerun and all succeeded.

How good of an indication of sstate-cache use is this information? If
I perform a successful build, delete sstate-cache, and then perform
the same build again Y is always some value greater-than zero. If this
NOTE at the end of a build was 100% a report of the sstate-cache
hit/miss rate, I would assume Y to be zero after a fresh build with no
sstate-cache, no?