2009-02-19
Lenny on a slug
As I've mentioned here before, I have a Linksys NSLU2 that I use as a home server. These ship with an embedded Linux system in their firmware, but they can be upgraded to run a full Debian system, making them much more capable. Mine has been running Debian 4.0 (Etch) since I got it.
A couple of days ago I ssh'ed into it to perform a regular software update. apt-get upgrade installed a new kernel, as it has several times before. So I rebooted it. And it failed to boot back into Linux. Since these things don't have any video hardware to reveal the details of the boot process, I've no idea what the problem was.
I interpreted this as a sign that it was time for an upgrade to Debian 5.0 (Lenny).
What I found impressive, considering the constraints and increasing age of the NLSU2, is that it is better supported in Lenny than it was in Etch. The Lenny installation is done using the normal Debian installer (you ssh into it). There's really not much more to it than installing Debian on a PC, though it is a lot slower (about four hours, apparently; I left it going overnight).
There's another noteworthy thing about it: Unlike Etch, Lenny for ARM comes with a recent 2.6.26 kernel with CONFIG_NOHZ enabled. And here is the vmstat output:
dwragg@bb5a:~$ vmstat 1 procs -----------memory---------- ---swap-- -----io---- -system-- ----cpu---- r b swpd free buff cache si so bi bo in cs us sy id wa 0 0 9060 1572 628 18004 0 0 20 8 18 63 0 0 99 0 0 0 9060 1572 628 18004 0 0 0 0 18 6 0 0 100 0 0 0 9060 1572 628 18004 0 0 0 0 16 8 0 0 100 0 0 0 9060 1572 628 18004 0 0 0 0 17 8 0 0 100 0 0 0 9060 1572 628 18004 0 0 0 0 18 12 0 0 100 0 0 0 9060 1572 628 18004 0 0 0 0 16 7 0 0 100 0 0 0 9060 1572 628 18004 0 0 0 0 17 5 1 0 99 0 0 0 9060 1572 628 18004 0 0 0 0 18 9 0 0 100 0 0 0 9060 1572 628 18004 0 0 0 0 19 13 0 0 100 0
Check out the in and cs values!