src, tool, and obj is on tmpfs Now.
It is 55% of time when src and tool are on Hard disk (4:25).

make release started at:  Wed Nov 18 20:35:46 JST 2015
make release finished at: Wed Nov 18 23:03:13 JST 2015
===> Successful make release
===> build.sh ended:      Wed Nov 18 23:03:13 JST 2015
===> Summary of results:
         build.sh command:    ./build.sh -j 6 -T /tmp/T.7.99.21 -R /export/R.7.99.21 -O /tmp/O.7.99.21 release
         build.sh started:    Wed Nov 18 20:35:33 JST 2015
         NetBSD version:      7.99.21
         MACHINE:             amd64
         MACHINE_ARCH:        x86_64
         Build platform:      NetBSD 7.99.21 amd64
         HOST_SH:             /bin/sh
         No $TOOLDIR/bin/nbmake, needs building.
         Bootstrapping nbmake
         MAKECONF file:       /etc/mk.conf
         TOOLDIR path:        /tmp/T.7.99.21
         DESTDIR path:        /tmp/O.7.99.21/destdir.amd64
         RELEASEDIR path:     /export/R.7.99.21
         Created /tmp/T.7.99.21/bin/nbmake
         Updated makewrapper: /tmp/T.7.99.21/bin/nbmake-amd64
         Successful make release
         build.sh ended:      Wed Nov 18 23:03:13 JST 2015
===> .
24408.86s 6715.07s 2:27:43.43 351% 0+0k 147+286287io 128555469pf+0w
n3150@makoto 23:03:13/151118(/tmp/netbsd-src)%