TuxOnIce is most easily described as the Linux equivalent of Windows' hibernate functionality. It saves the contents of memory to disk and powers down. When the computer is started up again, it reloads the contents and the user can continue from where they left off. No documents need to be reloaded or applications reopened and the process is much faster than a normal shutdown and start up.

TuxOnIce 3.0-rc7 for Linux 2.6 is out!

TuxOnIce has a long feature list, including the ability to cancel a suspend by pressing Escape, image compression to save time and space, a versatile plugin architecture, and support for machines with Highmem, preemption and SMP.

The TuxOnIce website (this one) and mailing list provide support for dealing with issues arising. An IRC channel #tux-on-ice has been created on irc.freenode.net, where people may be able to help you with problems.

The primary author of TuxOnIce is Nigel Cunningham. A huge thanks must also go to Florent Chabaud, Pavel Machek, Gabor Kuti, Bernard Blackham and Michael Frank along with many others who have tested and contributed to the development of TuxOnIce.

Current Versions

Here are the latest patches against 2.6 kernel series. 2.4 patches are currently unavailable due to reports of corruption problems with the most recent 2.4 kernels.

Git Trees:

Latest stable version for 2.6 kernels: 3.0-rc7

• TuxOnIce 3.0-rc7 for kernel 2.6.22.19
• TuxOnIce 3.0-rc7 for kernel 2.6.23.16
• TuxOnIce 3.0-rc7 for kernel 2.6.24.5
• TuxOnIce 3.0-rc7 for kernel 2.6.25

Latest stable version for 2.4 kernels^Note:

• There are currently no patches in this section.

Latest development version: 3.0-rc7a

• TuxOnIce 3.0-rc7a for kernel 2.6.26

  Note: See the Bugzilla page for known bugs with these patches.

These patches are released against the current kernel version, and regularly updated. They may contain bugs, and you are encouraged to report them into Bugzilla.

Latest TuxOnIce-UserUI: 0.7.2 [tar.gz] (What is TuxOnIce-UserUI?)

Latest hibernate script: 1.99 [tar.gz]

Older patches: Patches against older kernels are available from the Older Downloads section. These are generally unsupported though, and the archives are the best reference if you plan to use these. For really old work, you can consult the SourceForge archives but again be warned that nobody will be likely to help you.

Latest News

Although I haven't posted anything on the website for some time, I haven't been completely idle with respect to TuxOnIce. A look at the git archives (see above) will show a small but steady stream of patches being applied. I'm hoping to do one last release candidate soon, then 3.0. In the meantime, you can get up-to-date patches (as of today) for Ubuntu Feisty - Hardy and 2.6.22 onwards in the All downloads page. The file names start with "current-tuxonice".

I'm please to announce 3.0-rc7. rc6 was tagged but not released, hence the skip in version numbers. rc7 contains plenty of bug fixes and small improvements since rc5. Please see the email sent to the -devel list for a full changelog.

rc4 had a couple of small but important issues. In 2.6.23 and 2.6.24-rc8 vanilla kernels, there is a bug which changes between rc3 and rc4 expose, resulting in a hang at the atomic copy when resuming. This bug in vanilla has been fixed since 2.6.24-rc8, but not (to date) in 2.6.23. I'm therefore doing a new release with the fix added to the 2.6.23 patch. I'm not adding it to the 2.6.24-rc patch, on the assumption that those using the patch will be using the latest git. If you're still using rc8, please consider updating. There are other regressions fixed since 2.6.24-rc8 that you'll probably want.

The other fix is in code that controls the default configuration. I made a mistake that made the replace-swsusp-by-default compile time option ineffective, together with the full-pageset2 and late-cpu-hotplugging options (which would normally default to being on).

Wow. Is it that long since rc3? Oh well, I guess that shows that we're getting there. rc4 is now out, and the changes from rc3 mainly related to fixing speed regressions that some people reported in rc3. In addition, there's one new feature: support for running user space program/scripts, invoked from the kernel code before starting to hibernate and after completing resuming. These are intended to further the task of making TuxOnIce a drop-in replacement for swsusp. They could be used to run the hibernate script (modifications to it are in progress).

TuxOnIce 3.0-rc3 is now available. This release includes further bug fixes, and should thus be more even more reliable than rc2. It also includes new support for providing more understandable feedback on why preparing an image failed when that happens, and for recording the maximum memory use by TuxOnIce. The later was used to find a bug that would have been contributing to out-of-memory issues (the maximum outstanding i/o limit wasn't being fully honoured). There is also a bug fix for systems with large amounts of swapspace (among other bug fixes).

5 November 2007: 3.0-rc2.

TuxOnIce 3.0-rc2 is now available. This includes a number of bug fixes since rc1, and should be much more reliable, particularly under low-memory conditions. Versions for other vanilla kernels will appear as I complete testing (and after sleep).

TuxOnIce 3.0-rc1 is now available. Now that multithreaded I/O seems to be nicely settled, I think it's time to work towards a 3.0 release, so ... here's rc1.

2.2.10.3 came out without Nigel remembering to mention it here. Now a new release is development ready. This release adds further bug fixes. It has one known issue: reports have been received of problems with writing to encrypted swap since the fuse support was added. These will be investigated after this release is done.

Nigel is currently working towards a 2.2.10.3 release, which will include preliminary support for suspending while having fuse filesystems mounted. At the moment, there is no special support for fuse in Suspend2, which means that hibernating with fuse filesystems mounted may result in deadlocks.

Nigel has also been putting work into improving the lowlevel i/o code. Users who don't compress their images should hear the fan being significantly quiter in future releases, and users who haven't been getting throughput close to the maximum possible should see an improvement.

New releases of TuxOnIce's userui support and the hibernate script have been released. These are both in preparation for the 2.2.10.3 development release, which will be the first TuxOnIce release. /sys/power/suspend2 will become /sys/power/tuxonice from this release.

Suspend2 is changing its name. Recent discussions on the kernel mailing list have highlighted the importance of differentiating between suspending to ram and suspending to disk. To help make the difference clearer, Suspend2 is going to change its name to TuxOnIce. The transition will be gradual. Email will continue to use suspend2.net for a little while longer, but the web side of things has been switched over today.

2.2.10.2 (a development release) is out. This release introduces support for rtc wake alarms. Using this, you can (for example) set up your computer to write an image then suspend to ram. After 15 minutes, it could wake from suspend to ram and powerdown properly. It's also possible to do the reverse, having it powerdown immediately, then wake at say 6am, resume and then suspend to ram until you're wake and are ready to use it.

This version renames the resume2 file in /sys/power/suspend2 to resume; at the moment, you'll need updates to the hibernate script from svn or to manually edit your suspend2 scriptlet (assuming you're using the hibernate script) to use the new filename.

Richard Hughes' HAL website is a good resource for people who are trying to use HAL to initiate suspending or hibernating.

Thanks to Trevino, we also now have a patch for Ubuntu Feisty.

At long last, 2.2.10 is out. This patch release requires an upgrade to your userui support - release 0.7.1 is also now available. 2.2.10 leverages recently added support for doing cpu-hotplugging later in the process to provide support for multithreaded I/O. On SMP machines, this should result in a significant improvement in the speed of writing the image in particular.

I don't usually make announcements here for the development releases, but 2.2.9.5 is an exception. This release sees some of the bigger changes for a while in the Suspend2 codebase, with the addition of support for multithreaded I/O. I'm particularly excited about this change, because on my P4 based desktop machine (thanks, LAC Linux!), the speed at which Suspend2 can write a compressed image has improved by 50%! Previously I was getting stats like write: 60MB/s, read 90MB/s. Now they're about equal. This is because compressing an image is more cpu intensive than decompressing it, so we get a big improvement from being able to use both cores at the same time. Single-cpu users won't see a big improvement, sorry. We were already using your hardware to the max!

2.2.9.1 is taking a little longer than usual because Nigel has been preparing some new features. Support for building suspend2 as modules will make a come back, and there will be a new feature allowing you to resume a different image after suspending, instead of powering down. This might be useful in a lab environment, for example, allowing user sessions to be saved via suspend to disk on log out, with the system restoring an image to return to the login screen afterwards. Naturally, the normal limitations regarding having filesystems mounted in multiple filesystems will apply.

Work has also begun on adding support for suspending and resuming a cluster of computers.

Git trees which were temporarily removed (see next news item) have been restored. The work at fixing the site seems to have been progressing... or maybe not, depending on when in the day you try :).

Kernel.org servers are currently having great problems with load. While they wait for new hardware, I'm doing my bit to help ease the load by removing all but the branch against Linus' current tree from the list of publically available trees. If still want access to a particular tree, please let me know and I'll see what I can organise.

Nigel has starting blogging, at least occasionally.

The 2.2.9 release is now ready. Among other things, this release contains:

* one important bug fix, which stopped some users from being able to resume.

* modifications to the algorithm we use in deciding to save pages. By default, this new version will only save read-only process (LRU really) pages in the first part of the image. This will result in smaller images, which I expect complaints over :). The behaviour can be changed - see Documentation/power/Suspend2-Changelog.txt for more details.

* Removal of bdev freezing. Recent discussions with the XFS authors have led me to believe this is no longer required. Let's see how we go. If it is still needed, we'll see people hitting a BUG_ON(). No filesystem corruption will result.

Suspend2, version 2.2.8 is ready for download. This release requires version 1.93 or later of the hibernate script, as we've switched from /proc/suspend2 to /sys/power/suspend2. In addition, Suspend2 now contains support for being a drop-in replacement for swsusp. The following are now valid kernel commandlines for configuring Suspend2: resume=/dev/hda1, resume=swap:/dev/hda1, resume=file:/dev/hda1 and resume2=/dev/hda1 (as well as the older variants). Out of the box, Suspend2 is configured for LZF support (if selected at kernel compile time) and no encryption.

The 2.2.7 release is now available. This fixes some issues with 2.2.6. The use of the console suspend/resume code caused problems for some users. There is also a fix for a freeze when eating memory.

Suspend2, version 2.2.6 is now available, with the main changes in this version being in the area of bug fixes and cleanups. We now have a refrigerator implementation that is much closer to vanilla. Per-workqueue freezing is also gone for the moment. Neither of these changes should affect your ability to suspend. If they do, please report the bug and I'll seek to fix the issue quickly.

2.2.5 is now available. This release contains what I hope to be the last of the fixes after our switchover to using the lowlevel swsusp code. It also has more cleanups resulting from the ongoing preparation of a git tree. It's not far away.

2.2.4 contains a few more fixes after the changeover to using swsusp lowlevel code. The first fixes compilation issues with less usual configurations, and the second addresses an x86_64 specific problem that caused unreliability when resuming.

2.2.3 is now available. This is more tweaking and bug fixing after the swsusp changeover, along with a few other cleanups from my continuing work on building a git tree.

2.2.2.1 is a quick fix. In my rush to backport the changes for a particular person, I missed some changes to Makefiles in the arch specific directories. The simplest solution is to make Suspend2 force support for swsusp, so this version of the patch does that.

2.2.2 is now available. This is the first release to use the swsusp lowlevel code. The net effect is a reduction in the size of the Suspend2 patch, but at the cost of greater dependence on Rafael and Pavel not making incompatible changes.

2.2.1 includes a slew of cleanups and some bug fixes. Nothing overly exciting, sorry :)

I'm pleased to announce the arrival of Suspend2 2.2. There is, as always, still more work to do, but this exclusively in the area of bug fixes (especially improving non-x86 support). I now consider Suspend2 to be feature complete, and will be focussing on preparations for seeking to merge Suspend2 into the vanilla kernel.

rc16 is now available. AMD64 support is improved in this edition, and there are further cleanups and misellaneous bug fixes. Nothing exciting. I'm still pushing for 2.2.

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