gVirtuS allows an instanced virtual machine to access GPGPUs in a transparent way, with an overhead  slightly greater than a real machine/GPGPU setup. gVirtuS is hypervisor independent, and, even though it currently virtualizes nVIDIA CUDA based GPUs.

The software, developed for research applications, is provided as it is.

We encourage using and testing it in order to collect useful feedbacks and suggestions.

Take a look to the gVirtuS project page: http://osl.uniparthenope.it/projects/gvirtus/.

This is essentially a manual installation but thanks to DKMS, Dynamic Kernel Module Support, it isn’t required anymore to reinstall the driver at every kernel update.

Fedora 12 comes with the nouveau driver, I’m not saying that it isn’t good enough, but we have to force the system to don’t use it because only a driver at a time can manage a device. The first thing that we have to do is to blacklist the “nouveau” module to prevent that the kernel loads it automatically, to obtain this we should add the row to the file /etc/modprobe.d/blacklist.conf:

blacklist nouveau

and then rebuild the initrd image with dracut, using the following command:

dracut --force /boot/initramfs-$(uname -r).img $(uname -r)

Fedora 12 comes also with KernelModesetting, it’s a service that moves the graphics mode initialization from the X server startup to the kernel, and of course we need to disable it because it would load the nouveau driver. It’s possible to disable KMS adding the “nomodeset” option to the kernel boot parameters, so to obtain this we have to add the option nomodeset to (every) kernel entry in our /boot/grub/grub.conf. Fedora kernel’s post-install scripts are smart enough to add to the new kernel all the options used by the previous one, so it isn’t needed to add manually the “nomodeset” option when it will be installed an updated kernel.

Now neither the kernel or the KMS service would load the nouveu driver, we can nevermind about the xorg.conf because the nvidia-installer will create it later.

Now we can install the Nvidia driver, I’m using an x86_64 system and I want to use the version 190.42 of the Nvidia driver so I can download the package:

wget http://us.download.nvidia.com/XFree86/Linux-x86_64/190.42/NVIDIA-Linux-x86_64-190.42-pkg2.run

And we can run the following command to install the X Server related part of the driver:

sh NVIDIA-Linux-x86_64-190.42-pkg2.run --no-x-check --silent --no-kernel-module  --run-nvidia-xconfig

It’s possible to make the installation in graphic mode (ie runlevel 5) because we aren’t going to use the nvidia driver in this session: it wouldn’t be possible, the nouveau driver is loaded and has acquired the control over the graphic adapter.

Finally we can configure dkms for building and installing automatically the nvidia kernel module when the system boots. But of course it is needed to install dkms, and enable it:

yum install dkms
chkconfig dkms_autoinstaller on

DKMS can manage many modules with different versions too, each module’s sources are located in “/usr/src/-”, so we have to create the directory:

mkdir /usr/src/nvidia-190.42

copy the module sources (extracting them from the autoinstallable package) to that directory:

sh NVIDIA-Linux-x86_64-190.42-pkg2.run -x
cp NVIDIA-Linux-x86_64-190.42-pkg2/usr/src/nv/* /usr/src/nvidia-190.42/
rm -r NVIDIA-Linux-x86_64-190.42-pkg2

and create a file that instructs dkms on how build and install the module, the file is conventionally named dkms.conf:

#
# /usr/src/nvidia-190.42/dkms.conf
#
 
PACKAGE_NAME="nvidia"
PACKAGE_VERSION="190.42"
CLEAN="true"
MAKE[0]="make module"
BUILD_MODULE_NAME[0]="nvidia"
DEST_MODULE_LOCATION[0]="/kernel/drivers/video/"
AUTOINSTALL="yes"
 
# End Of File

In dkms.conf where sayng the name and the version of the module, to use “make module” as the make command, that the name of the built module is “nvidia” and that the module have to be installed automatically. (Note: we use “true” as the clean command because the default “make clean” would erase every object file, but some of them are closed source so we can’t recreate them.)

The last thing to do is to add the module to the dkms database with the command:

dkms add -m nvidia -v 190.42

.

and then reboot the system to use the nvidia driver.

That’s all folks!

When and Where

• Thursday, June 18
• 11:30 am onwards
• Location: University of Naples “Parthenope” – Faculty of Science and Technlogies, Centro Direzionale di Napoli Isola C4

Responsible Ambassadors

• Giuseppe Coviello

Attendees

1. Gianluca Varisco
2. … add yourself here! …

Program

• 11.30: “Welcomes to the conference” by Prof. Giulio Giunta
• 11.50: “Fedora 11, New Features” by Gianluca Varisco
• 12.20: “Free Software availment in italian universities” by Carlo Palmieri
• 12.40: “Presentation of the new magazine PaperUni” by Marielvira Matrone
• 13.10: “Open lunch and free speech”
• 14.30: “Workshop: realizing a scientific cluster using Fedora” by Giuseppe Agrillo
• 15.30: “About the NaLUG” by Gianfilippo Giannini
• 15.50: “The Fedora project, the community, the ambassadors” by Gianluca Varisco
• 16.20: “Future projects, distribution of gadgets and final regards” by Giuseppe Coviello

—

• 23.00: Party restarting at Arenile Reload

Organizers

• UDU Parthenope
• NaLUG – Napoli GNU/Linux Users Group

Contributors

• Associazione Palinsesto
• CRUX PPC

Contact

• Contact: Giuseppe Coviello (cjg@fedoraproject.org).

I feel interesting snapshots and clones primarily for backups: using a snapshot could be very trivial making a backup of the filesystem, moreover it’s possible making incremental backup with snapshots.

Although ZFS is developed primary for Solaris and OpenSolaris, it’s possible to use it on GNU/Linux through FUSE (Filesytem in Userspace), so it’s possible to use ZFS on GNU/Linux for all purposes (although could be very trouble using it for the root filesystem).

Fedora (10 or 11 ones) is pretty ready for using ZFS: it’s available a package (zfs-fuse) for ZFS-FUSE on the official repository, so the first step for using ZFS is installing this package with yum:

yum install zfs-fuse

Then it’s possible to create the pool of devices containing the filesystems and the filesystems; first of all I’ve created a pool on a partition of one of the harddisks of mine; before creating the book I’ve labelled the partition “ZFS” using “Palimpsest Disk Utility”, so I’ve created the pool with:

zpool create zfs /dev/disk/by-label/ZFS

And then the filesystems, setting the use of compression and disabling the storing of file access time:

zfs create zfs/home
zfs set compression=on zfs/home
zfs set atime=off zfs/home
zfs create zfs/home/cjg

Finally I’ve setted the mount point for the home filesystem:

zfs set mountpoint=/home zfs/home

Les jeux sont fait! From the next reboot I’ll use ZFS for my /home partition.

Now I had to create a new pool for storing the backups, I’ve created it on another partition of another disk (the partition is labelled “ZFSBACKUP”):

zpool create zfsbackup /dev/disk/by-label/ZFSBACKUP
zfs create zfs/home
zfs set compression=on zfs/home
zfs set atime=off zfs/home

I want that all backups will be stored on the zfsbackup pool and I want, also, to use incremental backups, so I’ve setted up a simple script for making incremental backups from the zfs pool to the zfsbackup pool:

#!/bin/bash
 
DATE=`date +%F-%H-%M`
zfs snapshot zfs/home/cjg@$DATE
zfs send -i latest zfs/home/cjg@$DATE > dump
zfs recv zfsbackup/home/cjg < dump
rm dump
zfs destroy zfs/home/cjg@latest
zfs rename zfs/home/cjg@$DATE zfs/home/cjg@latest
 
# End Of File

Simply it creates a snapshot of the zfs/home/cjg filesystem and calling it with the current date and time, then with “zfs send” it creates an incremental replication from the latest snapshot, then the replication it’s importend on zfsbackup/home/cjg, the latest snapshot on zfs/home/cjg is removed and the current snapshot is renamed as the latest.
In this way all the snapshot’s history is stored only on the zfsbackup pool.

Before using this script for the first time I had to create the “latest” snapshot on zfs/home/cjg and send it to zfsbackup/home/cjg with:

zfs snapshot zfs/home/cjg@latest
zfs send zfs/home/cjg@latest > dump
zfs recv zfsbackup/home/cjg < dump

To access a particular snapshot it’s possible to use:

zfs clone zfsbackup/home/cjg@2009-05-02-12-33 zfsbackup/home/2009-05-02-12-33

So it’s possible to access to the snapshot file through “/zfsbackup/home/2009-05-02-12-33″; of course it’s possible to use “zfs rollback” to restore the filesystem from a snapshot.

When the clone isn’t needed anymore it’s possible to remove it with

zfs destroy zfsbackup/home/2009-05-02-12-33