July 2009 Archives

I have a ThinkPad T61p Fedora 11 Linux laptop. Lately for some Linux training products we have been developing I've been doing alot of virtualization work on my laptop. Even though it has a fast dual core CPU, 8GB of RAM, and a fast internal 500GB SATA hard drive I've been seriously bottlenecked when I have a bunch of virtual machines doing lots of I/O. Some operations that normally take 20 minutes to complete have been taking 90 minutes. That is a serious productivity killer.

I need to add more hard drives and spread the I/O load across them. I would like to upgrade to a SSD drive, but I require 500GB capacity and although the just hit the market, it has several draw backs (besides the price) including using a MLC architecture. I briefly considered USB 2.0 hard drives but I knew that the USB 2.0 connection was a bottleneck

I decided to add an external eSATA hard drive using an ExpressCard eSATA controller.

Here are raw sequential I/O throughput the benchmark numbers on three drives. I tested the performance using hdparm -tT /dev/{sda,sdb,sdc}

Internal SATA SAMSUNG HM500LI 500GB
73.4 MB/sec

eSATA Western Digital WD10EVVS-63E 1TB "My DVR Expander"
85.1 MB/sec

USB 2.0 Lacie 120GB rugged
24.4 MB/sec

I used a Syba SD-PCBX-ESA2 ExpressCard SIL3132 Chipset 2x e-SATA II, 54mm. The great thing about Linux is that the controller was supported out of the box by Linux's sata_sil24 driver. I had nothing to install. I just plugged everything in and it all worked.

It would have been nice if my laptop had a built-in eSATA port. Hopefully my next Calpella platform based Thinkpad will have bottleneck free USB 3.0 ports and hopefully eSATA as well.

I've been running Fedora 11 on my T61p laptop, and I recently ran into the bug that caused repeated kernel oopes when running a NFS server and serving a bunch of data.

This bug has been fixed with the F11 kernel 2.6.29.6-213.fc11 which (as of July 9th, 2009) hasn't been pushed out yet (it is currently pending for fedora-updates-testing). I installed the new kernel and it has fixed the bug. Hurray for progress.

Unfortunately the yak shaving continues. I'm using RPM Fusion to get drivers for my Nvidia video card in my laptop. Since I'm running an unreleased kernel, the RPM Fusion repo doesn't have a matching kmod-nvidia package for the kernel portion of the Nvidia driver. My system automatically reverted to the VESA driver. Having the Nvidia libraries installed while using the VESA driver caused Unexpected signal: 11 problems for VMware workstation.

In order to build a matching kmod-nvidia package I performed the following (note I'm running 64bit Linux).

# yum install -y buildsys-build-rpmfusion-kerneldevpkgs-newest-x86_64

Now install the kernel-devel package for the newer kernel. I downloaded it from the Koji web page and manually installed it with rpm -ivh.

Download the newest nvidia-kmod.src.rpm from http://download1.rpmfusion.org/nonfree/fedora/updates/11/SRPMS/. Adjust the URL as needed for your version of Fedora.

Then, the command to rebuild the binary RPM that matches your running kernel is.

$ rpmbuild --rebuild nvidia-kmod-VERSIONINFO.src.rpm --define "kernels $(uname -r)" --target $(uname -m)

In my particular case it was:

$ rpmbuild --rebuild nvidia-kmod-185.18.14-1.fc11.1.src.rpm --define "kernels $(uname -r)" --target $(uname -m)