Initramfs fixes #6807

rlaager · 2017-11-02T03:04:05Z

Description

Besides the two minor cleanups (one whitespace and one typo), the point of this pull request is to make the initramfs script set elevator=noop on the root pool's disks.

ZFS already sets elevator=noop for wholedisk vdevs (for all pools), but typical root-on-ZFS installations use partitions. This sets elevator=noop on the disks in the root pool.

Ubuntu 16.04 and 16.10 had this. It was lost in 17.04 due to Debian switching to the upstream initramfs script.

How Has This Been Tested?

I originally tested the main code for this feature for Ubuntu 16.04, and it was integrated and has seen real-world use.

I tested this particular integration on an Ubuntu 17.10 system.

Types of changes

Bug fix (non-breaking change which fixes an issue)
New feature (non-breaking change which adds functionality)
Performance enhancement (non-breaking change which improves efficiency)
Code cleanup (non-breaking change which makes code smaller or more readable)
Breaking change (fix or feature that would cause existing functionality to change)
Documentation (a change to man pages or other documentation)

Checklist:

My code follows the ZFS on Linux code style requirements.
I have updated the documentation accordingly.
I have read the CONTRIBUTING document.
I have added tests to cover my changes.
All new and existing tests passed.
All commit messages are properly formatted and contain Signed-off-by.
Change has been approved by a ZFS on Linux member.

This fixes one instance of inconsistent whitespace. Signed-off-by: Richard Laager <rlaager@wiktel.com>

This fixes a typo in a comment. Signed-off-by: Richard Laager <rlaager@wiktel.com>

ZFS already sets elevator=noop for wholedisk vdevs (for all pools), but typical root-on-ZFS installations use partitions. This sets elevator=noop on the disks in the root pool. Ubuntu 16.04 and 16.10 had this. It was lost in 17.04 due to Debian switching to this upstream initramfs script. Signed-off-by: Richard Laager <rlaager@wiktel.com>

gmelikov

LGTM, thanks!

* initramfs: Fix inconsistent whitespace * initramfs: Fix a spelling error * initramfs: Set elevator=noop on the rpool's disks Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Reviewed-by: George Melikov <mail@gmelikov.ru> Signed-off-by: Richard Laager <rlaager@wiktel.com> Closes openzfs#6807

colmbuckley · 2019-07-16T10:46:38Z

This now fails with an error on Debian Buster with 4.19.37 kernel (as distributed); the "noop" scheduler does not seem to be included in this kernel:

lugh# cat /sys/block/sda/queue/scheduler
[mq-deadline] none
lugh# echo noop > /sys/block/sda/queue/scheduler
echo: write error: invalid argument

Should this now be using "none" with suitable tests? The code change is fairly trivial, but I don't understand enough about why the original change was made.

colmbuckley · 2019-07-16T11:04:25Z

Oh, seems that this is the distinction between multiqueue and non-multiqueue schedulers. What scheduler should be chosen in a multiqueue environment?

Assuming "none", something like:

                SCHEDULER="/sys/block/$i/queue/scheduler"
                if [ -e "$SCHEDULER" ]
                then
                        case $(cat "$SCHEDULER") in
                                *noop*) echo noop > "$SCHEDULER" ;;
                                *none*) echo none > "$SCHEDULER" ;;
                        esac
                fi

is probably the easiest fix.

colmbuckley · 2019-07-16T11:16:17Z

This is addressed #8004 - which I guess did not make it into 0.7.12. 0.7.13 should be hitting Debian in the next few weeks, so I guess it'll be fixed then.

This effectively reverts 4fc411f (part of openzfs#6807) and f6fbe25 (openzfs#9042) ‒ the code itself and latter PR cite symmetry with whole-disk-vdev behaviour (presumably because rootfs vdevs are rarely whole disks), but the code is broken for NVME devices (indeed, it'd strip the controller number instead of the (potential) partition number, turning "nvme0n1p1" into "nvmen1p1", which would then subsequently fail the sysfs existence check); it could be fixed to handle those (and any others) rather easily by dereferencing /sys/class/block/$devname, but this isn't the place for setting this ‒ as noted in the commit that removed setting the scheduler by default (9e17e6f) ‒ use an udev rule Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>

This effectively reverts 4fc411f (part of #6807) and f6fbe25 (#9042) ‒ the code itself and latter PR cite symmetry with whole-disk-vdev behaviour (presumably because rootfs vdevs are rarely whole disks), but the code is broken for NVME devices (indeed, it'd strip the controller number instead of the (potential) partition number, turning "nvme0n1p1" into "nvmen1p1", which would then subsequently fail the sysfs existence check); it could be fixed to handle those (and any others) rather easily by dereferencing /sys/class/block/$devname, but this isn't the place for setting this ‒ as noted in the commit that removed setting the scheduler by default (9e17e6f) ‒ use an udev rule Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz> Closes #11838

This effectively reverts 4fc411f (part of openzfs#6807) and f6fbe25 (openzfs#9042) ‒ the code itself and latter PR cite symmetry with whole-disk-vdev behaviour (presumably because rootfs vdevs are rarely whole disks), but the code is broken for NVME devices (indeed, it'd strip the controller number instead of the (potential) partition number, turning "nvme0n1p1" into "nvmen1p1", which would then subsequently fail the sysfs existence check); it could be fixed to handle those (and any others) rather easily by dereferencing /sys/class/block/$devname, but this isn't the place for setting this ‒ as noted in the commit that removed setting the scheduler by default (9e17e6f) ‒ use an udev rule Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz> Closes openzfs#11838

rlaager added 3 commits November 1, 2017 21:53

initramfs: Fix inconsistent whitespace

4767c7a

This fixes one instance of inconsistent whitespace. Signed-off-by: Richard Laager <rlaager@wiktel.com>

initramfs: Fix a spelling error

11b9dcf

This fixes a typo in a comment. Signed-off-by: Richard Laager <rlaager@wiktel.com>

gmelikov approved these changes Nov 2, 2017

View reviewed changes

behlendorf approved these changes Nov 3, 2017

View reviewed changes

behlendorf merged commit 34c2b36 into openzfs:master Nov 3, 2017

behlendorf added this to PR Needed for 0.7.4 in 0.7.4 Nov 3, 2017

behlendorf moved this from PR Needed for 0.7.4 to Merged to 0.7.4 in 0.7.4 Dec 12, 2017

colmbuckley mentioned this pull request Jul 16, 2019

ZFS: Unable to set "noop" scheduler #6513

Closed

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Initramfs fixes #6807

Initramfs fixes #6807

rlaager commented Nov 2, 2017

gmelikov left a comment

colmbuckley commented Jul 16, 2019

colmbuckley commented Jul 16, 2019 •

edited

Loading

colmbuckley commented Jul 16, 2019

Initramfs fixes #6807

Initramfs fixes #6807

Conversation

rlaager commented Nov 2, 2017

Description

How Has This Been Tested?

Types of changes

Checklist:

gmelikov left a comment

Choose a reason for hiding this comment

colmbuckley commented Jul 16, 2019

colmbuckley commented Jul 16, 2019 • edited Loading

colmbuckley commented Jul 16, 2019

colmbuckley commented Jul 16, 2019 •

edited

Loading