The 2026-09-11 trade bought a vendor-claimed 13-16% prefill figure that was
never measured here; the 2026-10-18 research (same decision record) shows what
identity mode actually costs the iGPU is the 1:1 page walk plus ATS/PRI/PASID/
GCR3 -- worth 2-4% on this silicon class, and removable outright by AMD PerfOpt
when the distro ships Linux 7.4. Meanwhile pt is what err=-19 asks for: the
XDNA2 NPU binds its own IOPT_TYPE_SVA domain and only needs the IOMMU enabled.
Measured off-vs-pt prefill arms follow in the docs commit; frank-archon
(Dankserver) is untouched.
/etc/default/grub was host-only state while the IOMMU boot line was the most
consequential kernel decision on the box (the 2026-09-11 amd_iommu=off adoption
lived only in the decision record). Fetched byte-exact (1581 B) and paired with
scripts/set-dankclaw-bootline.sh: refuses any host but dankclaw, shows the diff,
installs 0644 root:root, runs update-grub, names the pending token, and reboots
only on --reboot. The deployer plans nothing under dankclaw/host/ by design —
kernel state is not a container restart.
Frank