Kernel 2.6.31 is out and rocking!

This weekend I’ve had some free time so I tested a new kernel on my suse 11.1 x86_64 system. I’ve been a beta tester for the kernel for some time and I was eager to test the final version.

There are plenty new features, the one I enjoy more are probably on the filesystem area but there is plenty to choose.

This version adds USB 3.0 support, a equivalent of FUSE for character devices used for proxying OSS sound to ALSA, some memory management changes that improve interactivity in desktops, readahead improvements, ATI Radeon Modesetting support, support for Intel’s Wireless Multicomm 3200 Wifi devices, kernel support and a userspace tool for performance counters, gcov support, a memory checker for unitialized memory, a memory leak detector, a reimplementation of inotify and dnotify on top of a new filesystem notification infrastructure, btrfs improvements, support for the IEEE 802.15.4 network standard, IPv4 over Firewire, many new drivers, small improvements and fixes.

You may see the hole list here:

I still didn’t do extensive testing but so far so good ;), although my kde4.3  seams to lag a bit, I’m not sure if this is from the new kernel or the changes I’ve done within KDE itself.

On the other end with server machines it works perfectly, i’m doing stress tests on two virtual servers and memory usage / IO times / CPU usage.

On the test i’m using two opensuse 11.1 x86_64, one as 2.6.27 kernel version and the other 2.6.31, same amount of memory and 2 cpu each on the same host. Hope to have some more data in a few days and then post the results (cacti graphs) here if they are relevant.

So, what are you waiting for… TRY IT


Pedro Oliveira

Using fuse to mount a remote dir with sshfs


Today I’m writing about a little tool that is an enormous impact on  how to make a remote filesystem available to you as a local filesystem. You may be wondering, what’s the new? NFS does it, Samba does it, it’s true but if you don’t have a VPN and your away from your LAN or WAN a simple task like acceding a folder on a remote web server can be a pain.

The requirements on the host you need to access are:

  1. SSH server running
  2. User account

On the client side you’ll need:

  1. FUSE (Filesystem on user space) – you may install it easily with YUM, Zipper,apt-get, or whatever manager you’r using.
  2. sshfs – once again you can use your software manager or download it from
  3. On depending on the local mount point you may need root access.

Now before you start lets create a dir so you can have a local mount point:


and the mount command:


to umount REMOTE:

fusermount -u REMOTE

And your done .

There are a lot of options to sshfs, write/read under others permissions, sync or async writes, buffers sizes and read ahead options if you want to know more about all the options (and they are a few dozens) just type:

sshfs -h

Cheers and see you next time

Pedro Oliveira

ROS – Reboot oriented system

Today I’m at the office, not a usual thing in a Saturday, but a very production system in a client is being migrated.
The migration is from a Solaris 8 OS to Solaris 10 from a machine with 32 processors to 64 and from 64GB ram to 128 GB ram. Other significant change is the file system, the old one is the Veritas FS and the new one… ZFS (I really like it, I would love to have it on Linux outside of FUSE). You may read more about it on wikipedia.

We’re a few here on site right now just waiting for a Backup to end, but the nice thing is the 465 days up time this machine has… compared with the Sibel cluster that needs that it’s machines be rebooted every 2 hours… in a know OS. Or better in a very well known redmount ROS – Reboot oriented system.

I know that this isn’t a usual case and probably there are 20 different workarounds to solve those problems but the fact is if these workaround exist MS support doesn’t know them. So the workaround is a simple schedule reboot every 2 hours. And therefor the nickname for Win. 2003… ROS.