Disable udev

JOURNAL.md

@@ -4249,3 +4249,48 @@ Not sure which device is malfunctioning.
     UDEV  [1755.665632] add      /devices/virtual/tty/ptyaf (tty)
     UDEV  [1759.047259] add      /devices/virtual/tty/ptyb0 (tty)
 
+## 2024-09-27
+
+Here is the FPGA startup services by duration:
+
+    [root@nixos-riscv:~]# systemd-analyze blame
+    3min 59.980s systemd-udev-trigger.service
+     2min 6.780s suid-sgid-wrappers.service
+     2min 2.677s mount-pstore.service
+    1min 46.770s user@0.service
+    1min 10.554s systemd-journald.service
+     1min 5.538s resolvconf.service
+         48.660s systemd-logind.service
+         44.747s systemd-sysctl.service
+         43.971s sys-fs-fuse-connections.mount
+         43.358s dev-mqueue.mount
+         43.197s dev-hugepages.mount
+         43.043s sys-kernel-debug.mount
+         42.959s kmod-static-nodes.service
+         42.568s network-setup.service
+         42.546s modprobe@configfs.service
+         42.285s systemd-tmpfiles-setup-dev-early.service
+         40.980s modprobe@efi_pstore.service
+         40.510s sys-kernel-config.mount
+         39.891s modprobe@fuse.service
+         36.103s systemd-random-seed.service
+         30.686s systemd-udevd.service
+         30.059s systemd-modules-load.service
+         29.682s systemd-journal-catalog-update.service
+         29.091s systemd-remount-fs.service
+         26.090s systemd-tmpfiles-setup.service
+         23.570s systemd-journal-flush.service
+         21.042s systemd-tmpfiles-setup-dev.service
+         19.736s audit.service
+         17.794s systemd-update-utmp.service
+         15.329s dbus.service
+         10.177s modprobe@drm.service
+          9.866s systemd-update-done.service
+          8.302s user-runtime-dir@0.service
+          6.615s systemd-user-sessions.service
+          5.384s network-local-commands.service
+          4.933s getty@tty1.service
+
+It doesn't make much sense to have udev on the FPGA, as we are not going to
+hotplug anything. Maybe I can just disable the service, and save 4 minutes (at
+least).

lagarto-ox.nix

@@ -14,8 +14,8 @@
   # We don't need any firmware
   hardware.firmware = lib.mkForce [];
 
-  #services.haveged.enable = true;
+  # No need for udev
-  #services.jitterentropy-rngd.enable = true;
+  services.udev.enable = false;
 
   # Prevent executing the nscd program as it seems to hang the CPU
   system.activationScripts.users = lib.mkForce (