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Feature #532

Installer support for ZFS compression

Added by Albert Lee almost 9 years ago. Updated about 7 years ago.

Status:
New
Priority:
Low
Assignee:
Category:
Caiman (Installer)
Target version:
-
Start date:
2010-12-16
Due date:
% Done:

0%

Estimated time:
Difficulty:
Medium
Tags:
needs-triage

Description

Caiman should support ZFS compression and (for gui-install) adjust the minimum required disk space accordingly.

History

#1

Updated by Julian Wiesener over 8 years ago

  • Assignee set to OI Caiman

remember that this may cause problems if you compress /boot

#2

Updated by Albert Lee over 8 years ago

GRUB supports ZFS compression, so there aren't any known issues with booting from a compressed root pool. I've been doing it since ZFS boot support was added.

#3

Updated by Yan-Cheng Zhang over 8 years ago

In my memory, compression=on(equals lzjb) was supported only.

#4

Updated by Jim Klimov about 7 years ago

  • Difficulty set to Medium
  • Tags set to needs-triage

I checked with oi_151a5 - creating a gzip-9 compressed dataset and rsyncing contents of a snapshot of the current rootfs into it resulted in a bootable system (with manual additions to GRUB's menu.lst). This dis not boot when I tested the same technique a couple of releases ago (GRUB refused to read the root dataset).

"zfs set compression" and "zpool set bootfs" do still protect the user from combining compression with bootability, though this can be worked around trivially. I think these checks are now obsolete, or rather they need updating to allow those combinations that are known to work with grub (of current release with assumed-known features, or better somehow query grub's capabilities) - and by default protect users against other combos, including algorithms unknown to this given release of the OS.

#5

Updated by Jim Klimov about 7 years ago

Apparently, GRUB can also try to protect itself, by disliking the non-off value of compression on "rpool/ROOT" - complains of inconsistent disk structure. One way or another, working with a compressed complete rootfs did not prove stable after all. Yesterday it booted several times, today it complains of inconsistent disk structures...

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