Just for the record in case anyone reads old bug reports:
* By default Debian 9+ uses systemd, which has borged bootchart's
functionality into itself:
systemd-analyze plot >tmp.svg
* By default Debian 9+ ramdisks are *not* systemd, so
exactly the same problem (no bootchart profiling for ramdisk stage) is
still present.
* You can fix this by switching from initramfs-tools to dracut
(since dracut uses systemd by default), but
this has its own problems:
* Debian Live doesn't support dracut (yet)
* crap hooks, so e.g. dracut needs bash, but the ramdisk is not
rebuilt when bash gets a security upgrade.
* crap dependencies, so e.g. dracut *in theory* can use busybox
instead of bash, but lots of its modules have an undeclared
dependency on bash, and if you remove bash, those modules fail
at boot time in exciting ways.
* dracut ramdisks are EVEN BIGGER and EVEN SLOWER than the
initramfs-tools ramdisks
* dracut is written in bash (like initramfs-tools), and ignores
errors instead of aborting. So if something goes wrong
building the ramdisk, you don't find out until you try to
reboot and discover your system is no longer bootable.
