About the Role
Yahoo’s Linux Operating System team is looking for a Systems Engineer with kernel development experience. This job involves building, patching, performance evaluation and tuning of the Linux kernel. The candidate will be involved in hardware validation of Linux releases and participation in upstream and vendor communities. The overall goal is to support infrastructure needs by providing a secure and scalable operating system for cloud and non-cloud properties to build on.
Please apply for the position here http://j.rfer.us/YHODt-BAD (referral link). Feel free to contact me regarding the position at firstname.lastname@example.org
This years Flock conference was held at Prague, czech republic. This was my first trip to the Europe. I needed a Visa for this trip unlike my American friends. I got the visa in the last minute from the Consulate of czech republic, Los Angeles. The Visa officer needed an insurance of minimum 50000 Euro with Medical reparation and Evacuation converge. My company Yahoo was able to get that sorted in time. I attended lot of talks and workshops at Flock. I took notes on some of the sessions i attended. Here is my conference report
Status of COPR build service – by Miroslav suchy
COPR is an automatic build system to build rpms. COPR allows users to select
Arch and system (target) , accepts src.rpm from the user and generates binary
rpms in the backend and creates repo as well.
Unlike koji COPR doesn’t need a ‘fas’ account to build rpms. Technically any one
can build rpms on COPR.
Due to public nature of COPR it uses Virtual Machines to build rpms. A virtual machine
is setup and mock is used inside the VM to build the rpm.
COPR currently runs on openstack. There are 1381 projects, 25k builds, 250 G of data,
and 1 TB/month data transfered in COPR as we speak. Koji/OBS was evaluated to use in
COPR but the decided against it for some reasons. OBS signing daemon might be used
with COPR to sign rpms in future.
* Mock is kind of slow, there is a GSOC project to speed it up using LVM snapshots *
* Radek Holy is working on docker for rpm builds *
It is important to note that redhat software collections are built on COPR. There
is a jenkins plugin available for COPR which lets users to trigger COPR builds
from jenkins. There is a copr-cli available to builds.
ARM architecture support, package signing are in future TODO.
Here is the video of the talk
UEFI – The great satan and you – by Adam
I am a fan of UEFI. I have been closely following UEFI development and support in Linux for a while. If you do not know about UEFI, Adam Williamson has an impressive write up about it at https://www.happyassassin.net/2014/01/25/uefi-boot-how-does-that-actually-work-then/
Adam started with what is UEFI and then moved on to explain how older BIOS works. Adam’s talk focused on Desktop machines
How BIOS work?
- Boots the 1st sector of disk
– The bootloader is sneaked in between MBR and the partition
- Defines an EFI executable format.
– EFI executable is copied into FAT filesystem and the firmware can read it
– UEFI boot manager is used to change the boot order and EFI variables.
– There is a fallback path if the EFI executable is not found on the specified path
– Supports BIOS mode named CSM. CSM is going away soon.
Adam proposed following tests to tell if your machine is UEFI?
- Machine is Windows 8 pre-installed. Then it is must have UEFI in it.
– The “firmware” has mouse support then it is UEFI (BIOS can’t do that sh*t)
Adam showed some screenshots of crazy UEFI firmware UI implementations that makes identifying it more difficult for the user.
While multibooting adam asked the users to install both OS in same mode. Mixing BIOS (CSM) and UEFI is discouraged and unsupported in Fedora.
Adam then proposed following special commands to write a USB stick with EFI support
- dd: use dd on usb sticks
– livecd-iso-to-disk: pass –efi –format -reset-mbr
– liveusb-creator: well..it might work
– DO NOT use Unetbootin
Adam then revealed that, Peter Jones and Matthew Garret lobbied Microsoft to enable option to disable secure boot. They even have weekly calls. The engagement with microsoft has been very professional. Microsoft takes UEFI signing seriously.
I asked peter about completely removing microsoft key from the firmware. He said it is a “bad” idea because ROM based firmwares won’t load and they are signed by the Microsoft key. He also mentioned that there is a complex workaround to this problem. The workaround is generating the hash of the firmware and adding it to the shim whitelist.
Here is the video of the talk
Fast OS Deployment with Anaconda – By Arun S A G (me)
I presented and showed a demo on how to deploy operating systems fast on bare metal
machines. The entire talk was well received by the anaconda team.
The demo showed installations of a Fedora 21 (pre release) VM which took 2 minutes
to complete. Most of the audience were pleasantly surprised.
- There were some interesting thoughts and area for improvements came out of this talk
- RedHat developer proposed me to make use of the cloud kickstart file which has very minimal set of package
- Peter Jones suggested that anaconda can/should be modified to produce tarballs as one of the build targets (anaconda right now supports iso targets)
- Most of the installation time was spent on generating ramdisk. So peter suggested we should pre-generate the ramdisk and include it in the tarball.
- rpmdb cache needs to be removed from the tarball.
- Adam williamson asked me to share some sample kick-start files from work so that we can well test different use cases before releasing anaconda.
- Automating the biosboot partition during the installation process was discussed
Here is the video of my talk
Overall it was a wonderful conference. Thanks Yahoo and RedHat for sponsoring my travel and accommodation. It was good to see lot of volunteers again and i had a good time in Prague, Czech republic. I am looking forward to Flock 2015
This is kind of a late post. I spoke at Flock. It was about “Fedora At Yahoo!” – How we use Fedora in desktops and laptops at Yahoo!
Here is the presentation http://sagarun.fedorapeople.org/misc/FedoraAtYahoo.pdf
I have a pair of them now. On April 1 (yes, fools day ) i got my lasik laser surgery done. I am writing my experience down here without my spectacles ;-) hope it is useful to some of you who want to do the surgery.
I took a leave of absence from work for a week before the surgery. I consulted a doctor in Aravind Eye Hospital ,Tirunelveli a small city near my home town and decided to get it done there.
I had my pre surgery check up on March 30 (saturday), They took cornea topology scan on both eyes and analyzed my cornea’s thickness. I had around 580 micron thick cornea which is good enough to do a laser surgery. The doctor suggested me to do zyoptix laser instead of ordinary laser. Zyoptix uses wavefront guided laser technology and claims to fix refractive errors which cannot be fixed by other lasers. I asked the doctor about complications, she mentioned about halos and starbursts but didn’t mention about scary things like ectasia but it was mentioned in the agreement that i signed before the surgery. The hospital doesn’t have a “bladeless” surgical option ( i.e there is no femtosecond laser) but the doctor is experienced so i decided to trust her hands with microkeratome. The hospital does refractive surgery on Wednesday’s and Friday’s, i asked them to prepone it to Monday (April 1) they were able to accommodate my request.
Surgery’s are done early in the morning so i was asked to come to the hospital 7’o clock in the morning. We reached the hospital little late thanks to my dad’s driving :-) I was asked to have breakfast before the surgery. After the breakfast i was asked to sign an agreement which basically says no one is responsible if my eyes are screwed. I was asked to remove my shoes and asked to enter the waiting room (room in front of the surgery room) Then i was asked to wear a long gown and a cap to cover my hair. I was also given anesthetic eyedrops before i entered into the surgery room. In the surgery room three scary people were waiting for me with masks over their lower face, covering their mouths and noses. I was asked to lay down on a moving surgical bed, top of the bed had a curve where i could just fit my head. Now one of those scary people covered my face with a sheet. The sheet had a opening that just came right on top of my right eye. It also had a tape like thing , they used to it hold my eyelids so i don’t close them during the surgery. Another nurse used a clamp to enlarge my eye. This was bit uncomfortable.
The doctor, moved the bed back into the laser equipment. The equipment had very bright lights focused at my eyes, it was uncomfortable for me to be under those lights. I would normally use profanity at people who don’t dim their main beam headlights while driving. But these lights were 3-4 times worse than those. The setup had a green and red color light accompanied by those very bright main beam headlights. You could imagine a big alien spaceship on top of your head flashing lights at you. I was asked to look at the red color light to reduce the discomfort. In the mean time the doctor was cleaning my eye and a big equipment was kept on top my eye holding it (microkeratome) . The doctor asked me not to move my eye. (Hello, how can you not roll your eyes when you have a big a** light focusing straight at you ) I heard a wheel rotating sound and could feel something being cut. In my opinion this is the scary part of the surgery. The microkeratome is like your lawn mower but it cuts and creates a flap on the eye. See this video on how it works. I was informed that the lights would go off and asked not to panic. By the time the lights were back on i was asked to focus on the red light again. After the lights were back on i could smell something burning The smell was from the laser shaping my cornea tissues. Once the shaping was done my eye was cleaned with a really cool liquid. The flap was lifted back up was placed in its place. They took a two minute interval before moving on to the second eye.
While doing the second eye i was little bit tensed (because now i know what they gonna do to my eye). More over the doctor was asking about another patient during the interval in a yelling voice (WTF? ) The nurse messed up the clamp so they had to remove the clamp and put it back on and the doctor made a sound that indicated something was messed up (more likely subconjunctival hemorrhage). IMO a doc should not make this kind of sound while the patient is conscious and in surgery. I was shit scared still didn’t open my mouth, as it might add up to the tension. The same procedure was done to the left eye. Once everything was done i was asked to get up and go to the inspection room. The doctors assistant helped me remove the gown and cap. The doctor came back into the inspection room and inspected my eye (flap) again. Everything was normal. The whole procedure took 10 minutes and it was painless. I was asked to wear a protective glass to protect my eye from dust and accidental rubbing. I stayed back in the hospital on the day of surgery. The next morning my eye was examined and my visual acuity was 20/20 . I could read the last line on the board with some help. I was asked to come back for examination after a week for further evaluation. After a week i could read the last line without any help.
After the surgery, first three days are critical because the flap sticks there just using osmotic pressure. It can easily dislocate. I was asked to not to look at TV/Computer for five days. I was given with a steroid (Gatilox GM) (2 weeks) and a lubricant (Systane ultra) for dry eyes.
I had surgery induced dry eyes and subconjunctival hemorrhage. Dry eye problem was severe for the first 2 weeks. I even had head aches because of that. I kept using the lubricant to keep my eyes wet. My eyes became tired in the evenings. I am writing this post three weeks after the surgery, the dry eye problem is almost gone now eyes are not getting tired as earlier. But i have problems with night vision. I have glare problems with Fluorescent lights. I also see halos. These are indications that the flap is not completely closed yet. Night driving is difficult too. I will post more information here as i get better with night vision.
So Is lasik worth the risk? I am still not sure. You will have to evaluate the risks and current conditions before doing the surgery. Lasik has a long healing period unlike what they advertise. For 5% of people the lasik surgery can result in ugly complications. As long as you are not in the 5% everything is fine. Now that’s the risk you will have to take :-)
OSX crashed on me while i was trying to update firmware. Instead of recovering it, i decided to install Fedora 18 on my MacBook.
I had made couple of Fedora 18 x86_64 DVD’s for the Fedora freemedia program. I grabbed one of them and started the installation to find myself dropping into a prompt. Apparently it is one of known issues with the Fedora 18 CD/DVD. After typing in ‘(cd0,apple3)/EFI/BOOT/grub.cfg’ the installation started. There was no problem with the installation.
I am used to natural scrolling, enabled it using the following setting
$ cat /etc/X11/xorg.conf.d/99-wt-natural-scroll.conf
Identifier “Natural Scrolling”
Option “ZAxisMapping” “5 4″
I like my function keys, following sets the fn keys as primary in the apple keyboard
$ cat /etc/modprobe.d/hid_apple.conf
options hid_apple fnmode=2
Above option also can be passed using kernel command line. You will have to edit the grub.cfg for that /boot/efi/EFI/fedora/grub.cfg
By default Fedora 18 didn’t detect my broadcom wireless network card (Broadcom Corporation BCM4331 802.11a/b/g/n (rev 02) to be exact) It needed a proprietary firmware. I downloaded b43-firware module from “russian fedora” http://pkgs.org/fedora-18/russian-fedora-nonfree-i386/b43-firmware-5.100.138-1.fc17.noarch.rpm.html and installed it. After the reboot things started working.
The proprietary driver doesn’t seem to support power management, it may cause problems during suspend/resume operation. So i instructed the power manager to unload the module while suspending the machine
$ cat /etc/pm/config.d/defaults
GNOME 3 Desktop often doesn’t get show up after unlocking the screen https://bugzilla.redhat.com/show_bug.cgi?id=878736 If it happens press CTRL+ALT+F2 , login via tty and run ‘DISPLAY=:0 gnome-shell –replace’
The new kernel kernel-3.8.2-206.fc18.x86_64 panics while booting on MacBook Pro https://bugzilla.redhat.com/show_bug.cgi?id=922175
The newest version of python-requests now supports python 3. The python 3 version of requests is available as python3-requests package. Thanks Rex Dieter for the patch https://bugzilla.redhat.com/show_bug.cgi?id=807525 . I have also decided to maintain python-requests for EL6, i have pushed the latest version 0.11.1 to EL6.
Though it violates the updates policy https://fedoraproject.org/wiki/Updates_Policy, i have updated python-requests from 0.6.6 to 0.10.8 in Fedora 16 as python-requests is a fast moving young project.
All the packages should land in updates-testing in a few days. Please visit https://admin.fedoraproject.org/updates/python-requests to learn more about the updates.