Tested on amd64 laptop in a chroot. Without noble-proposed:
```
$ schroot-wrapper -c noble -u root -p
initramfs-tools,cloud-initramfs-copymods,cloud-initramfs-rescuevol,cloud-initramfs-dyn-netconf,cloud-initramfs-growroot,cloud-initramfs-rooturl,cloud-initramfs-updateroot,overlayroot,hyperfine,linux-image-generic
# hyperfine "update-initramfs -u"
Benchmark 1: update-initramfs -u
Time (mean ± σ): 7.952 s ± 0.232 s [User: 2.699 s, System: 5.750 s]
Range (min … max): 7.539 s … 8.394 s 10 runs
# lsinitramfs /boot/initrd.img > /files
# dpkg -l | grep -E
'(cryptsetup|initramfs|dracut|open-iscsi|lvm2|thin-provisioning-tools|overlayroot)'
ii busybox-initramfs 1:1.36.1-6ubuntu3.1
amd64 Standalone shell setup for initramfs
ii cloud-initramfs-copymods 0.48 all
copy initramfs modules into root filesystem for later use
ii cloud-initramfs-dyn-netconf 0.48 all
write a network interface file in /run for BOOTIF
ii cloud-initramfs-growroot 0.48 all
automatically resize the root partition on first boot
ii cloud-initramfs-rescuevol 0.48 all
boot off a rescue volume rather than root filesystem
ii cloud-initramfs-rooturl 0.48 all
use a tarball or squashfs image in a url as the root filesystem
ii cloud-initramfs-updateroot 0.48 all
extract a tarball over root filesystem before pivot
ii cryptsetup 2:2.7.0-1ubuntu4
amd64 disk encryption support - startup scripts
ii cryptsetup-bin 2:2.7.0-1ubuntu4
amd64 disk encryption support - command line tools
ii dracut-install 060+5-1ubuntu3.2
amd64 dracut is an event driven initramfs infrastructure (dracut-install)
ii initramfs-tools 0.142ubuntu25.1 all
generic modular initramfs generator (automation)
ii initramfs-tools-bin 0.142ubuntu25.1
amd64 binaries used by initramfs-tools
ii initramfs-tools-core 0.142ubuntu25.1 all
generic modular initramfs generator (core tools)
ii libcryptsetup12:amd64 2:2.7.0-1ubuntu4
amd64 disk encryption support - shared library
ii libklibc:amd64 2.0.13-4ubuntu0.1
amd64 minimal libc subset for use with initramfs
ii overlayroot 0.48 all
use an overlayfs on top of a read-only root filesystem
```
With noble-proposed:
```
$ schroot-wrapper -c noble -u root -p
initramfs-tools,cloud-initramfs-copymods,cloud-initramfs-rescuevol,cloud-initramfs-dyn-netconf,cloud-initramfs-growroot,cloud-initramfs-rooturl,cloud-initramfs-updateroot,overlayroot,hyperfine,linux-image-6.8.0-41-generic
-e
# hyperfine "update-initramfs -u"
Benchmark 1: update-initramfs -u
Time (mean ± σ): 7.647 s ± 0.277 s [User: 2.631 s, System: 5.502 s]
Range (min … max): 7.139 s … 7.973 s 10 runs
# dpkg -l | grep -E
'(cryptsetup|initramfs|dracut|open-iscsi|lvm2|thin-provisioning-tools|overlayroot)'
ii busybox-initramfs 1:1.36.1-6ubuntu3.1
amd64 Standalone shell setup for initramfs
ii cloud-initramfs-copymods 0.49~24.04.1 all
copy initramfs modules into root filesystem for later use
ii cloud-initramfs-dyn-netconf 0.49~24.04.1 all
write a network interface file in /run for BOOTIF
ii cloud-initramfs-growroot 0.49~24.04.1 all
automatically resize the root partition on first boot
ii cloud-initramfs-rescuevol 0.49~24.04.1 all
boot off a rescue volume rather than root filesystem
ii cloud-initramfs-rooturl 0.49~24.04.1 all
use a tarball or squashfs image in a url as the root filesystem
ii cloud-initramfs-updateroot 0.49~24.04.1 all
extract a tarball over root filesystem before pivot
ii cryptsetup 2:2.7.0-1ubuntu4.1
amd64 disk encryption support - startup scripts
ii cryptsetup-bin 2:2.7.0-1ubuntu4.1
amd64 disk encryption support - command line tools
ii dracut-install 060+5-1ubuntu3.2
amd64 dracut is an event driven initramfs infrastructure (dracut-install)
ii initramfs-tools 0.142ubuntu25.2 all
generic modular initramfs generator (automation)
ii initramfs-tools-bin 0.142ubuntu25.2
amd64 binaries used by initramfs-tools
ii initramfs-tools-core 0.142ubuntu25.2 all
generic modular initramfs generator (core tools)
ii libcryptsetup12:amd64 2:2.7.0-1ubuntu4.1
amd64 disk encryption support - shared library
ii libklibc:amd64 2.0.13-4ubuntu0.1
amd64 minimal libc subset for use with initramfs
ii overlayroot 0.49~24.04.1 all
use an overlayfs on top of a read-only root filesystem
# lsinitramfs /boot/initrd.img > /files
```
The creation time is slightly faster and diffing the content of the
initrds show no difference:
```
diff -u /run/schroot/mount/noble-*/files
```
So verified the SRU successfully.
** Tags removed: verification-needed verification-needed-noble
** Tags added: verification-done verification-done-noble
--
You received this bug notification because you are a member of Ubuntu
Touch seeded packages, which is subscribed to initramfs-tools in Ubuntu.
https://bugs.launchpad.net/bugs/2065180
Title:
performance regression in dracut-install 060
Status in Dracut:
New
Status in cloud-initramfs-tools package in Ubuntu:
Fix Released
Status in cryptsetup package in Ubuntu:
Fix Released
Status in dracut package in Ubuntu:
Fix Released
Status in initramfs-tools package in Ubuntu:
Fix Released
Status in lvm2 package in Ubuntu:
Fix Released
Status in miniramfs package in Ubuntu:
Fix Released
Status in open-iscsi package in Ubuntu:
Invalid
Status in thin-provisioning-tools package in Ubuntu:
Fix Released
Status in cloud-initramfs-tools source package in Noble:
Fix Committed
Status in cryptsetup source package in Noble:
Fix Committed
Status in dracut source package in Noble:
Fix Released
Status in initramfs-tools source package in Noble:
Fix Committed
Status in lvm2 source package in Noble:
Fix Committed
Status in miniramfs source package in Noble:
New
Status in open-iscsi source package in Noble:
Fix Released
Status in thin-provisioning-tools source package in Noble:
Fix Released
Bug description:
[ Impact ]
When compared to Ubuntu 23.10, creating intramfs files with update-
initramfs takes 2 to 5 times more time on ARM devices.
IIUC, dracut-install usage was added to initramfs-tools to speed up
the process. But now its way slower. Even running update-initramfs on
jammy, which doesn't use dracut-install, is way faster then the time
taken on Noble.
first bad commit -
https://github.com/dracutdevs/dracut/commit/3de4c7313260fb600507c9b87f780390b874c870
Updating the initrd on a Raspberry Pi Zero 2W on Ubuntu 24.04 (noble)
with initramfs-tools 0.142ubuntu25.1 takes over six minutes:
```
bdrung@zero2w:~$ sudo hyperfine --warmup 1 -r 10 "update-initramfs -u"
Benchmark 1: update-initramfs -u
Time (mean ± σ): 402.751 s ± 5.592 s [User: 166.316 s, System:
228.909 s]
Range (min … max): 394.380 s … 411.445 s 10 runs
```
[ Test Plan ]
1. Measure `update-initramfs -u` before the update.
2. Log the content of the initrd before the update: `lsinitramfs
/boot/initrd.img`
3. update dracut-install / initramfs-tools-core
4. Measure `update-initramfs -u`. It should be faster (the performance
improvements on amd64 should be very small and might be within the measurement
uncertainty).
5. Check with lsinitramfs that the content of the newly generated initrd
hasn't changed.
[ Where problems could occur ]
The code that is responsible for including the kernel modules into the
initrd is touched. Negative consequences could be that some needed
kernel modules will not be included any more (should be covered by the
test case) or that building new initrds will fail.
The initramfs-tools fix changes how manual_add_modules behaves.
`manual_add_modules` does not copy kernel modules, but queues them for
being copied when the newly added function `apply_add_modules` is
called.
I checked all instances of calls to `manual_add_modules` for possible
regressions (see comment #15). Only miniramfs needs to be adjusted to
also call `apply_add_modules`. But this change could break consumers
of the `manual_add_modules` function that are outside of the Ubuntu
archive. I googled for `apply_add_modules` but found no public outside
users.
[ Benchmarks ]
Stock noble on a Raspberry Pi Zero 2W:
```
bdrung@zero2w:~$ sudo hyperfine -r 5 "update-initramfs -u"
Benchmark 1: update-initramfs -u
Time (mean ± σ): 415.664 s ± 6.015 s [User: 166.728 s, System: 232.523 s]
Range (min … max): 409.139 s … 422.632 s 5 runs
```
noble with dracut-install 060+5-1ubuntu3.1 (with linux 6.8.0-1006.6 on
2024-07-01):
```
bdrung@zero2w:~$ sudo hyperfine --warmup 1 -r 10 "update-initramfs -u"
Benchmark 1: update-initramfs -u
Time (mean ± σ): 248.054 s ± 5.569 s [User: 67.410 s, System:
169.412 s]
Range (min … max): 238.909 s … 257.384 s 10 runs
```
noble with dracut-install 060+5-1ubuntu3.2 (with linux 6.8.0-1007 on
2024-07-11):
```
bdrung@zero2w:~$ sudo hyperfine --warmup 1 -r 10 "update-initramfs -u"
Benchmark 1: update-initramfs -u
Time (mean ± σ): 232.001 s ± 5.678 s [User: 55.456 s, System: 166.510 s]
Range (min … max): 222.120 s … 239.610 s 10 runs
```
[ Reduce manual_add_modules calls ]
Besides making the dracut-install calls faster, group the dracut-
install calls. Since the fix in oracular can cause regressions in
custom hooks that rely on the current behavior, the SRU takes a safe
approach which includes following packages (stating how many dracut-
install calls are used):
* cryptsetup: 2 -> 1
* lvm2: 8 -> 1
* thin-provisioning-tools: 3 -> 1
* open-iscsi: 9 -> 1
* cloud-initramfs-tools: 5 -> 1
dracut-install calls on a Raspberry Pi Zero 2W:
| area | before | noble SRU | oracular |
|--------------------------------------|--------|-----------|----------|
| auto_add_modules + apply_add_modules | 8 | 5 | 5 |
| calls by hooks + apply_add_modules | 42 | 20 | 2 |
| hidden_dep_add_modules | 1 | 1 | 1 |
| total | 51 | 26 | 8 |
[ Other Info ]
$ lsb_release -rd
No LSB modules are available.
Description: Ubuntu 24.04 LTS
Release: 24.04
$ apt-cache policy dracut-install
dracut-install:
Installed: 060+5-1ubuntu3
Candidate: 060+5-1ubuntu3
Version table:
*** 060+5-1ubuntu3 500
500 http://ports.ubuntu.com/ubuntu-ports noble/main arm64 Packages
100 /var/lib/dpkg/status
To manage notifications about this bug go to:
https://bugs.launchpad.net/dracut/+bug/2065180/+subscriptions
--
Mailing list: https://launchpad.net/~touch-packages
Post to : touch-packages@lists.launchpad.net
Unsubscribe : https://launchpad.net/~touch-packages
More help : https://help.launchpad.net/ListHelp
