Up and Running

Replaced my old colo machine with a newer IBM X335 SCSI RAID1 based system this afternoon. Usually story, things never go according to plan.

I’ve replaced my User-Mode-Linux based system with XEN. Seems to work well. There are a few performance issues. I think though this is mainly network related. All the disk direct benchmarks I’ve done so far seem to indicate similar performance for the host and guest domains. Of course, since the Host is itself a guest of of the hypervisor it doesn’t running completely at native speeds. Unfortunately I didn’t spend the time doing some disk benchmarks for non-XEN kernels. However the “buffered disk reads” figures I posted previously should be the almost twice as much for a SCSI U160 system.

No matter, at least its better than the glum and glue I was using previous. I’m use the XEN guys will get around to improving this performance in due course. Anyway the performance in the guests is better than a UML based system, and I never really had much luck with the Linux vserver project.

If my back wasn’t giving my some issues at the moment, I’d probably make a short list of issues I had while upgrading and reinstalling the guest OSs. Then getting the applications (include wordpress) back up an running. For instances, took me a while to realise that mysql.so was commented out in php.ini by default. I was fiddling around with mysql GRANT tables, and all manor of other stuff. WordPress needs a better error message for this situation, more like the phpmyadmin. While on the subject of MYSQL Grant tables, this page is a the main reference on the various different levels (column, table, database, global) of privileges.
Anyway a list of these later.

4 Comments

  1. Richard Parry Said,

    March 10, 2005 @ 11:59 am

    Shame about your back – best get that sorted, at least whilst you’ve got “free” healthcare before your trip ๐Ÿ™‚

    BTW – thinking about this recently, have you thought about SOlaris (either sparc or x86) for the UML/XEN requirements? Solaris 10 has off the shelf implementation of micropartitioning (containers or zones). Worth a thought, if XEN doesn’t do everything you want – Solaris will, and now does virtual LPARs without needing hardware support in the CPU.

    It’s also now got a lot of nice GNU tools bundled, and becomes more Linux-like by the day, but with corporate backing and support. Worth a look if you’re in the hole and what you’ve got just isn’t doing it for you. Sun stuff Just Works ™.

  2. Nicholas Lee Said,

    March 11, 2005 @ 8:08 am

    I’ve read about Zones, but I can’t say I thought about running it. Solarias isn’t really on my radar for production use as I’ve tended to think that its hardware support on x86 is not as good as Linux. The performances will probably sort themselves out, and in fact I can run something similar to Zones with Linux-Vservers. I’m not really a fan of this though. The other thing about Solarias, is that although its GNU toolchain support is pretty good, I’m a bit lazy and can’t be bothered being forced to compile apps that in Debian I can just apt-get.

    Finally, I guess if I’m happen to be on the other side of the world I need to be able to visual what’s happening in the machine with much thought. It will be a while before I can do that with Solarias.

    I’ve got XEN working now. Had to chase not a default configuration bug that was generating 200,000 interrupts per sec in the bridging code. Stability was affected and there wasn’t much performance hit. So you can see that XEN is pretty robust. I think I need to add a second processor to my new machine before I see the true benefit of running this over the old Dual Xeon Racksaver with UML. Disk is definitely far better, but terminal performance can be a little laggy at times. As you would expect when it’s switching on the same processor between different OS contexts.

    Once I’ve got that sort, the next project is a (free)NX based Ubuntu desktop. ๐Ÿ™‚

  3. Richard Parry Said,

    March 12, 2005 @ 10:16 am

    Fair enough, but I’ll just run through a couple of things for you.
    1. Solaris’s x86 support does indeed blow, but you’d be a numbnuts to buy a standard PC to run it on when Sun make such excellent, fast, and robust Athlon-based 64-bit x86 machines for so cheap. The benefit of Solaris is not just that it’s a great UNIX, but because Sun make arguably fantastic hardware, with good innovation, excellent support, and a scalable architecture (which extends to their x86 line of 64-bit cores). We just got a dual-proc x86 machine from them and it’s _beautiful_, to the point where the Windows guys are wanting to trial it for running their shit on. Very comparable – cost-wise – to Dell, IBM, and other branded server companies.
    2. Blastwave.org is all you need. SunFreeware.com is also good, but if you like apt-get then the blastwave project is for you. Painless, and integrates Debian’s package management system for free tools into the Solaris package schema. Think of it as Fink for Solaris, because that’s pretty much what it is.
    3. Solaris IS system5. Using Solaris 2.8, aside from a few filename differences, is very similar to Debian – indeed, Debian IMO is more similar to Solaris than it is to RedHat Linux.

    Maybe next time you’re down I’ll bring you into work and let you cruise around one of our dev boxes, just have a look at how they work. [shrug] If Xen works for you then keep using it, but those Sun engineers are smart fuckers to be sure. With their new x86 low-end servers they deliver a compelling UNIX experience across the board at all price points.

    Sure, I sound like a marketing droid, but I love the platform. My two favourite UNIX platforms are Solaris and Mac OS X, for mostly different applications. But with both – well, I don’t have to fuck around just to get basics working, they both Just Work ™.

  4. Nicholas Lee Said,

    March 12, 2005 @ 10:31 am

    In the end that is the main thing. Using what you known and love. Debian is almost like the back of my hand these days. Looks like Novell will be shipping Xen in the next version of SuSE Linux Professional. Seems its pretty ready for prime time. I’m trying it much cleaner to use than UML, all they to sort out is a couple security configuration issues. You need to hack some python or iptable some ports to stop the xcs and system console redirects ports being internet visible.

    On another note, one thing I’m disliking about OSX is its terminal and the two replacement terminal programs. Is there something better? Have you trying getting KDE/Konsole to work? Given that I got a 1.7GHz P-M, 1Gb, 60Gb, 15″, R-51 Thinkpad for less that $3000 for my brother I’m being tempted back to the x86-side. Even though the Mini Mac I got is cool, I not really feeling the pull to use it as a default workstation.

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