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Fedora Docs Directly in your Electronic Reader

Publican, which is the software that generates Fedora Documentation, now supports OPDS, the Open Publication Distribution System. OPDS is a syndication format for electronic publications. Thus, Electronic Reader programs or devices can be given a URL for the Fedora Docs catalog, and can browse through it, and download publications for reading.

If you have a program that supports OPDS, add in the URL http://docs.fedoraproject.org/opds.xml, or if you want our preference…US-English, try http://docs.fedoraproject.org/en-US/opds.xml.

We use Aldiko,  an ebook book reader for the Android mobile OS. But there are several more. For a list of some complaint readers, click here.

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Published on October 5, 2010
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Simple Power Management Under Fedora

SATA-Kabeladapter
Image via Wikipedia

This post is a result of experimentation, but also of some information from the RHEL6 Power Management Guide. Most people tend to ignore power management, but remember, power management can result in lower utility bills as well as increased life of components.

First, turn on CPUSpeed if it isn’t on. It may require enabling BIOS settings. Look for names like SpeedStep, Cool’n’Quiet, PowerNow!, ACPI, SMART to enable in BIOS. Then, set CPUSpeed to run. CPUSpeed dynamically adjusts the speed and voltage of the CPU based on demand.

While you’re in BIOS, take the opportunity to disable any system piece you aren’t using. For example, your parallel port.

Tuned is a daemon that monitors the use of system components and dynamically tunes system settings based on that monitoring information. A detailed system configuration might be too time-consuming for most. Most people will not do certain things unless it is easy and does not inconvenience them too much. Thus, tuned comes with preset profiles.

Active-State Power Management (ASPM) saves power in the Peripheral Component Interconnect Express (PCI Express or PCIe) subsystem by setting a lower power state for PCIe links when the devices to which they connect are not in use. ASPM controls the power state at both ends of the link, and saves power in the link even when the device at the end of the link is in a fully powered-on state.

Aggressive Link Power Management (ALPM) is a power-saving technique that helps the disk save power by setting a SATA link to the disk to a low-power setting during idle time (that is when there is no I/O). ALPM automatically sets the SATA link back to an active power state once I/O requests are queued to that link.

tuned has the following profiles:

  • default – lowest impact on power savings, only enables CPU and Disk Power Savings
  • desktop-powersave – designed for desktops. Enables CPU, Disk, and Ethernet savings, as well as ALPM power saving for SATA.
  • server-powersave – Designed for Servers. Enables ALPM powersaving for SATA host adapters, disables CD-ROM polling through HAL (refer to the hal-disable-polling man page) as well as the CPU and disk power controls.
  • laptop-ac-powersave – medium-impact profile for laptops on AC. Enables CPU, ethernet, disk, wi-fi, and ALPM power saving for SATA.
  • laptop-battery-powersave – high-impact profile for laptops on battery. All the same from the AC-powersave, plus multi-core power-savings
    scheduler for low wakeup systems and makes sure that the ondemand governor is active and that AC97 audio power-saving is enabled. Will work for any system, not just a laptop, there will be a noticeable impact on performance.
  • throughput-performance – server profile for throughput performance. Disables power saving mechanisms and enables sysctl settings that improve the throughput performance of your disk and network I/O, and switches to the deadline scheduler
  • latency-performance – server profile for typical latency performance tuning. It disables power saving mechanisms and enables sysctl settings that improve the latency performance of your network I/O.

To list available profiles,  use the command tuned-adm list.

To switch to another profile, use tuned-adm profile profile_name.

Reducing the amount of work performed by the hardware is the best way to save power. Applications that request unnecessary work prevent hardware from entering a reduced state. Fedora has already done a lot of work in reducing unnecessary processes, but it can’t do everything. Audit running processes and discontinue anything unnecessary.

But, let’s address one concern. By turning things off or slowing them down, it means you may have a few seconds wait while they reactivate. That may be a downside, but the secret is to find a balance between always on and always off. It is better to turn it on than leave it off. Plan well early on.

We’ll have more on this later.

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Published on July 19, 2010
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SouthEast Linux Fest is Over

This weekend, our Editor was down at the SouthEast Linux Fest in South Carolina. Three fun filled days of interacting, speakers, vendors, free stuff, and oddly enough, playing board games. The panels put a lot of interesting thoughts on the table, and over the coming weeks, we plan to discuss a few of them.

These sort of discussions always light a fire under us. Already, we’ve started hardening our servers in various ways, started looking at a new way to explain MythTV to the guys over at HTPCentric, got scared about IPV6, etc.

SELF’s speakers were all filmed, and the video will be available eventually. We’ll post links when available.

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Published on June 15, 2010
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Planning for and Optimizing Solid State Drives

This past week, we installed our first Solid State Drive. We had a lot of concern about this technology early on. There were reports of gradual performance degradation.This has been improved, however, and we’ll discuss some ways to better optimize your experience. Hopefully, in future Linux releases some of these options will be configured automatically

The biggest development that has been made to preserve longevity on these drives is TRIM. The TRIM command allows the operating system to inform the drive which data blocks are no longer in use and can be wiped. TRIM is supported beginning in kernel 2.6.33 and can be enabled under Linux by editing the mount options to include the discard option, such as in the below example.

/dev/sda1 / ext4 discard,defaults

Other suggestions include removing journaling and limiting read and writes to the drive. This will extend life as well, but without journaling, there is some risk of data loss in the event of a crash. However, Theodore Tso debunked this thought last year in a blog post, in which he concluded that the overhead is minimal.

  • Another Linux-based tuning technique is to disable Linux from writing the last accessed time to files. This can be done by adding noatime to the above command. Realistically, on many computers the last accessed time is not extremely important. Do not confuse accessed time with the last modified time.
  • Add the option elevator=deadline to your grub boot configuration to use the deadline disk scheduler. If you have a slower CPU go for the noop scheduler. The default schedulers are optimized for traditional hard drives.
  • Move your Firefox Cache to RAM – Open Firefox and enter about:config in the location bar.  Right-click and choose the option New->String.  Enter “browser.cache.disk.parent_directory” for the preference name, and for the string value enter “/dev/shm/”. That will also reduce writes and improve performance.
  • Reduce kernel swappiness(the tendency for the OS to swap from physical memory to a hard drive based swap file). Add vm.swappiness  = ? to /etc/sysctl.conf. Default is 60, out of 0-100. Some suggest lowering it all the way to 0. Experiment with what works for you. This suggestion is not limited to systems with SSDs.

Bear in mind for the Firefox and Swappiness suggestions, you should have enough RAM to support reducing the swap and moving the cache to memory.

Now that we’ve covered optimizing the solid state drive, let’s discuss usage. We used the Kingston 30GB SSD, reviewed here in comparison to the Intel value SSD, which we also considered. The SSD, because of price and size considerations, is not ideal for all functions. You can see a picture of it just before install in the laptop we used to write this blog entry above.

SSDs are small in size, but speedy. Their best use is as an operating system drive. In our first test case, which is a laptop, they are the only drive. However, the laptop is mostly OS only. All media and other files are stored on a file server. With this drive, the laptop flies along and is extremely quiet as an SSD makes no noise. We have not done any battery life tests, but there is some evidence from those who have that some SSDs may be less energy efficient than conventional hard drives.

In conclusion, with the price of SSDs continuing to drop, it is a good time to start considering it as a boot/OS drive for your systems. Now that we’ve grown comfortable with its usage, we plan on expanding it to future renovations, including in our file server.

Update(06/03/10): The day after we wrote this, AnandTech released a review of three SSDs, including our Kingston 30GB as well as the Onyx and Intel budget SSDs. Certainly makes us feel better about our purchase.

Published on June 2, 2010
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LightScribing and Fedora

A LightScribe disc label printed with Wikipedi...
Image via Wikipedia

LightScribe is nothing new.  It has been around for years, We like the idea. After all, no one can read our handwriting anyway. And we want something that looks nice, but it easy to generate. A simple label making program that allows us to type the information and have it burned to the top of the DVD or CD seems ideal.

There are problems though. Lightscribe discs shouldn’t be stored in direct sunlight. It is recommended they be stored in polypropylene disc sleeves rather than PVC sleeves, and even certain residual chemicals on your hands can cause discloration.

For the record, the same technology, but not compatible, is available in the competing standard of  LabelFlash, which has some of the same problems. Neither of them offer color…yet.

The surprising thing is that this technology isn’t more prevalent. Of course, there is pricing to consider. We went to discounter Meritline.com to check on pricing. A 25 pack of Philips Lightscribe DVD+Rs costs $7.99, or about 32 cents a DVD. A 50 pack of regular Philips DVD+Rs costs $15.50, or about 31 cents a DVD. We picked Philips because they are about average quality. Either way, going Lightscribe isn’t going to break the bank.

Even with that, you can get DVDs for less if you look around. Our last DVD purchase was 100 Sony DVDs at 20 cents a DVD during a Staples sale. We hand label such things. But we keep a spindle of lightscribe CDs and DVDs, and do burn them occasionally.

What prompts us thinking about this again? Fedora has released a complete set of Lightscribe labels. They’ve produced LightScribe versions before, but this is the first time they’ve generated versions of all their labels, regular and Lightscribe, for all of the release versions, the various Live Disks and the Installation DVDs, as well as the blank label so you can add your own text.

Their label isn’t ideal for Lightscribe, which needs high contrast, but they’ve made the effort, and even without the background, the text and Fedora bubble logo made our burn look professional. We will have our Fedora review coming up soon, but we’ve had some trouble with it on our netbook, the first system to receive the upgrade, and want to fiddle a bit before getting to a second computer.

Published on November 19, 2009
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Fedora 11 for Servers

It is time to talk about our Fedora 11 server migration. Why, do you ask, are we discussing this three months after Fedora 11 was released, halfway to the release of Fedora 12?

We finally upgraded our server to Fedora 11 this morning, after a weekend of work. In previous generations, we’d offloaded all of the data, formatted all the drives, and installed the new OS. And we, to keep up, would have to do this every 6-9 months, every time a new Fedora release came out. And our data kept growing. When you are storing many gigabytes of information, trying to slowly offload to a 4.3GB DVD is a slow process.

This weekend, we threw in the metaphorical towel, and got a 1.5TB drive and installed it in the computer. This allowed us to empty our older drives one by one and reformat them to EXT4 format. We had previously been using the more established XFS format. EXT4 is an update of the established EXT3 with improved handling for large files, among other things.

Improved large file handling is very important to us, because we use our server as a storage base for our MythTV DVR. Large file handling is required when an hour of over-the-air broadcast HD can be more than 8GB.

After reformatting all the drive to EXT4, we discovered another feature we’d never noticed before. The Reserved Block Percentage for the Superuser. A default setting, it holds back 5% of the reported available drive space for superuser privileged processes, ensuring that even if the hard drive fills up, the running processes can still do their work. Which is all well and good on an OS partition. But on a data partition, 5% of  a TB drive is almost 50GB being held in reserve. Ultimately, now that we know it is there, we left it turned it. You can override it as needed.

While we kept all the data on the data drives, although we did move around what was stored where, we did wipe and redo the OS partition completely. This is always a learning experience because as we rebuild parts of it, we add and fiddle with features, some of which are new to the upgraded OS. For example, we added an hourly run of status information which is ported to Linux’s MOTD(Message of the Day) feature so that anyone logging in receives a notification of them.

We also tried running tuned. Tuned isn’t enabled by default under Fedora 11, and it is merely an early version of a project that should be fully realized in Fedora 12. For several versions, Fedora has been auditing programs to look for redundancy or inefficiency. One of the most solid examples of that was a goal of a 20-second boot time.  There is an apparent lack of good discourse on tuned that we found, but the service will allow cpu, disk, and net devices to adapt dynamically to usage, reducing power, according to profiles set.

Tuned, unfortunately, kept bringing down our network link, causing hiccups. For now, we’ve turned it off. Power Management is a goal we aspire to. We want constant availability with low power usage, which means a service that turns things off when not in use. We look forward to the next generation of this program, when it may be enabled by default.

Since our server does not run a graphical environment by default, nor does it have a monitor attached normally, the experience of using it is different than most using a Linux machine. We’re always looking for things to cut from it to improve its efficiency. During this latest iteration, we cut a partition, no longer creating a separate home partition for the system. We never store anything in the home directories anyway.

You will be hearing more about our server. Our systems are the testbed for practical experiments in spinning down hard drives and other techniques to try and reduce waste. The drives are even 5400rpm ‘green’ drives, as the data doesn’t require anything faster. If you are interested in more specific details about the system, comment. We’d love to hear your feedback.

Published on September 15, 2009
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Fedora and Netbooks

In a recent blog post, Michael Dehaan, a software developer comments on his experience with the Ubuntu Netbook Remix versus Fedora 10. Dehaan points out that Fedora could learn a lot from it.

We can’t disagree. Openness and sharing is what Linux is all about. Fedora doesn’t have a spin for netbooks. There is a Special Interest Group for “Fedora Mini”, which was originally intended for netbooks, but has the expanded focus of other devices.

A lot of the work in a mini distribution is reducing dependencies. While hard drive space makes extra program installation not as much of a problem, current trends toward speed, efficiency, and bandwidth limiting suggest that we should be looking at this. For example, Fedora installs Bluetooth services on a system regardless of whether or not there is a bluetooth adapter installed. It installs smart card authentication on everything. And the default option during an installation is to configure software packages after installation, not before.

Michael seemed to have a lot of trouble with Fedora on Netbooks. We did not with our little MSI Wind. Initially, there were no drivers for the wireless card, but we were able to compile them. Then, because we don’t like unstable drivers, even if they did work, we swapped the stock card for an Intel one with great Linux support.

We’ve tried Ubuntu Netbook Remix, and it does offer a lightweight environment and a good launcher. But there are good launchers available of similar design available for Fedora. The lightweight LXDE environment is available through Fedora, as is XFCE, which in its latest version has a more traditional GUI design than its predecessors.

The fact is that we must agree and disagree. What Fedora lacks is a good lightweight spin. Which is a shame. Fedora has all the tools to be lightweight with personal tweaking.

There are things in the works though. The Fedora LXDE spin is set to be offered as part of Fedora 12, and an XFCE spin which has been offered for several iterations of Fedora.

What we would like to see, and perhaps we should suggest it, is increasing the number of default setup profiles in the default DVD installation, or allowing a custom profile to be loaded in. Currently, the Kickstart process, which is designed mostly to automate administrator installations for multiple systems, allows for this, but we’d like to see a Fedora supported initiative in this direction. A minimalist server profile, a minimalist desktop profile, etc.

Ubuntu offers a Desktop and a Server LiveCD as its primary installation media. We like the fact Fedora offers both this and a DVD where the most popular softwares can be installed on multiple systems without repeated downloads. We just think that the default installation needs to be streamlined, or offer the options to be streamlined without having to hack together a customer version of Fedora or download multiple different LiveCDs. We, as we said, could do this using Kickstart, but we’d like it if Fedora took the lead on it as well.

That said, the full version of Fedora 11 works wonderfully on our netbook, and while we’ve tried Ubuntu Netbook Remix on an Eee…we’ll stick with what we are familiar with.

Published on July 13, 2009
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Fedora 11 – Palimpsest Saves the Day

Fedora Linux 10
Image by Dekuwa via Flickr

Yesterday, those of you following our tweets know that we continued our Fedora migration plan. The plan was sidetracked when the new Fedora 11 monitoring advised us of a hard drive problem.

SMART, System Monitoring and Reporting Tool, is built into every hard drive, and does not seem to be utilized under Windows(feel free to correct us on this. It might be hiding there somewhere). Linux has always offered a monitoring daemon, but now that is coupled with Palimpsest Disk Utility, a frontend to the disk functions of DeviceKit, so alerts come to the desktop. DeviceKit is a replacement for the older HAL system, and creates a uniform interface.  “This is a simple system service that a) can enumerate devices; b) emits signals when devices are added removed; c) provides a way to merge device information / quirks onto devices.”

So, after letting it do a check to confirm, we swapped out the drive, and used it as an excuse to clean the interior of the computer and add extra ventilation, and resumed installation.

The two machines done are part of our MythTV system, where simple computers take the place of cable boxes, so nothing is stored on the drive except the software. All the video comes over the network from the backend(the last machine to get Fedora 11). But had the hard drive contained critical data, this feature would have prevented a major disaster.

In a disappointment, both machines, which run Nvidia video, did not work with Plymouth by default, but the boot on them is so fast you hardly see the splash screen anyway.

As a final measure, the remaining Fedora 10 machine will now download its updates directly from the internet, allowing us to delete our 30GB Fedora 10 Repository. The Fedora 11 machine will continue to use the assembled Fedora 11 repository.

The remaining machine is the hardest because it is where all the data is stored. Fedora Upgrade Time is a time to think about new hardware. Perhaps a hard drive might need to be replaced, etc. Migration of large amounts of data is difficult. The system must be slowly backed up and emptied, using a combination of optical burns, backup hard drives, etc. It will take a bit more work.

We continue to find new things to love about Fedora 11. The continual improvement to hardware handling is one of them. More to come.

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Published on June 18, 2009
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First Thoughts: Fedora 11

Image representing Fedora as depicted in Crunc...
Image via CrunchBase

We plan to offer more thoughts later, as we will be doing some field-testing. We have installed Fedora 11, code named Leonidas on a MSI Wind U100 netbook which we will be taking with us on a trip this weekend, allowing us to explore it before rolling it out to other systems.

Our initial impressions are that F11 is a winner. It has been cleaned up at every level. We installed it from scratch and proceeded to install everything we routinely use on a mobile system, including Firefox(with Xmarks, formerly Foxmarks to store our bookmarks), Dropbox for our Documents and some configuration files, and Adobe Air so we can run our Twitter client. There was a problem with Adobe Air, but a quick net search found us the solution(a symbolic link so Air could find a library). The whole process took very little time.

Plymouth, Fedora’s graphical boot loader, now supports Intel based graphics cards, which are found in a majority of productivity based notebooks and netbooks. Since our previous systems didn’t support it by default, and we saw no need to override that, this is the first time we’ve seen the graphical loader outside of one try. Plymouth is plug-in capable for different boot screens. The default one is merely a circle that gradually fills in until it is complete. We’ll have to take a look at the alternatives there as well.On the other hand, it is a boot screen. We don’t want to spend too much time looking at it, especially if it slows things down to render something fancier.

Fedora also has changed the default volume group name to include the hostname…a minor touch, and the ext4 file system. Anaconda, the Fedora installer, continues to be fairly user-friendly. Fedora has rebuilt many areas of the program, but the feel is pretty much the same for installation.

Into the OS itself, Fedora 11 had a goal of a 20-second boot time. It isn’t quite achieved on a netbook, but it came fairly close. The netbook is the only system we use that doesn’t support the 64-bit architecture, so we used the 32-bit, which has now been rebased as i586 instead of i386 We also enabled Presto to reduce update sizes. On our first update, we had a 91% download savings with no noticeable problems.

The new versions of Gnome and Firefox look subtly different, but we haven’t had a chance to experiment with them yet, beyond configuring things the way we want them. We will report back on this.

Finally, as this is a mobile computer, Fedora 11 boasts new power saving measures, including an update to the handling of relatime backkported from the 2.6.30 kernel, which was just released, but after the Fedora 11 release. We look forward to seeing how these power measures enhance battery life.

So, in the end…Fedora, better than ever, no show-stopping problems we’ve seen so far…and more to come.

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Published on June 11, 2009
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Fedora 11 Delayed by One Week

A Screen Shot of Fedora 8
Image via Wikipedia

To our disappointment, the Fedora 11(Leonidas) launch date has pushed back by one week. As noted on their announcement mailing list….

In a meeting today between Release Engineering, QA, and various team
leads, we decided to enact a 7 day slip of the Fedora 11 release date.
The primary reason behind this slip is the state of our blocker bug:
https://bugzilla.redhat.com/showdependencytree.cgi?id=F11Blocker&hide_resolved=1 We cannot begin Release Candidate phase until the blocker bugs are closed or at least in MODIFIED state. We are not there today, which would be our last day to enter RC phase and still have enough time to release on the 26th. We hope to enter RC phase in the next couple days, and hit our new target, June 2nd.

Freeze breaks for critical bugs will still be accepted, however trivial
bug fixes should be pushed as updates via bodhi. Thanks!

Better to have a stable system than an unstable one. Here’s hoping for June release.

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Published on May 20, 2009
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