BenV's notes

Yesterday evening after getting tired of playing the Aion open beta (it was the last night of the open beta, so we felt like at least reaching level 10, which we did… and then we could ~FLYYYY) we decided to go downstairs to watch some series on our beamer. So we fire up the machine connected to it, which runs everything from NFS. It didn’t take long for the boot screen to come up and after the default selection was made for us it ran through the boot process spewing out the usual kernel messages….. (continue reading…)

Lately I’ve heard some rumors about this new mmorhghhghg coming up called “Aion“.
Fileplanet (you know, the cancer popup site you sometimes get when you need to download a game patch and then need to click through 23894723897 registration things etc… which is barred from bugmenot…. *sigh*) handed out open beta keys. So I got one. And so did lotjuh.

Did I mention my machine doesn’t have windows? Makes it… interesting.
First we obviously tried wine. Well, it installs without much hassle, which is a good thing.
However, it doesn’t launch. Some piece of garbage called GameGuard doesn’t work on wine. And because it doesn’t, neither does Aion.
Great going Aion guys! Needless to say they couldn’t be arsed to write a linux binary for it, so they SUCK per default! They couldn’t even be arsed to write a Mac binary for it. Pffrt.

However, to make an interesting attempt to test out Virtualbox’s 3d acceleration support, I decided to install Aion in a virtualboxed windows xp that I “borrowed” from lotjuh.
Virtualbox is at version 3.0.6 these days, so first I installed the latest version.
The installation went fine:

Not only the installation, but also the updater ran fine:

Then the gameguard part came, it looked promising:

However, to all good things must come an end. So it dies because of hardware acceleration issues. No real surprise, but too bad for Virtualbox. Not there yet.

Maybe it’ll work one day when Virtualbox gets their direct3d working as well as wine has it working.

Anyway, from what I’ve seen of the game (it runs ‘fine’ on lotjuh’s PC with her “Seven” failure install), it’s a World of Warcraft wannabe.
Graphics are a lot better, they put in some cute stuff like when it rains and the character idles it’ll put a leave over their head. The movies are cute, the quests sometimes even show you stuff (like a little ingame movie of the target area) to go along with the text. But all in all it doesn’t look like a wow killer. No linux support (not even with wine), no mac support, and so far I haven’t seen a major reason for people to switch from wow to this game, except for the graphics. Then again, I’ve only looked at it for a short amount of time, maybe it’ll get better 😉
I’m sure they’ll get a decent amount of players though, it’s a good wow clone.
Story wise the game is fail, I could sum it up with “There were gods, and a planet, and now the planet is split in 2 half planets and the ‘people’ on those halves fight eachother”.

It asks for a stellar converter if you ask me. (master of orion 2 reference, can’t find a good image/video on google)

Yesterday I found a release notice in the pulseaudio mailinglist announcing version 0.9.16.
Today, I found another release note in the mailinglist that announced pulseaudio version 0.9.17. Gee, another fuckup? (but that’s part of the release process I guess ;))

Anyway, I decided to upgrade my 0.9.15 installation since it still glitches every now and then. (continue reading…)

So yesterday at work I ran into the famous ssh MAC failure like this:

wouter@wouter-laptop:~:0> rsync -varP ./vmware/ wouter@192.168.1.2:/archive/archive2/programs/vmware/
Password:
sending incremental file list
./
Keys
116 100% 0.00kB/s 0:00:00 (xfer#1, to-check=8/10)
linux/
linux/VMware-server-2.0.1-156745.i386.tar.gz
32768 0% 800.00kB/s 0:10:11 Received disconnect from 192.168.1.2: 2: Corrupted MAC on input.

rsync: writefd_unbuffered failed to write 4 bytes to socket [sender]: Broken pipe (32)
rsync: connection unexpectedly closed (53 bytes received so far) [sender]
rsync error: error in rsync protocol data stream (code 12) at io.c(600) [sender=3.0.6]


No, that has nothing to do with Apple/Mac computers or Media Access Control, it’s
part of the SSH protocol (and others) called Messenge Authentication Code. This blog has a nice explanation: Jan Pechanec on SSH messages.

Funny thing, my brother also had this exact issue with the same kind of laptop. Well…. in his case it was putty failing his connection from a windows machine to this laptop.
The reason? Same as ever, checksum offloading.
You can check if your card does this with the ethtool program:

wouter@wouter-laptop:~:0> sudo ethtool -k eth0
Offload parameters for eth0:
Cannot get device flags: Operation not supported
rx-checksumming: on
tx-checksumming: on
scatter-gather: on
tcp-segmentation-offload: off
udp-fragmentation-offload: off
generic-segmentation-offload: on
generic-receive-offload: off
large-receive-offload: off


And the fix for this:

wouter@wouter-laptop:~:85> sudo ethtool -K eth0 tx off

Fixed.

” Wait, what does Pokemon OS have to do with this?”
Well, isn’t that obvious? It’s supposed to magically work, and it doesn’t! 😉
Probably more a kernel thing though… oh well.

After toying around a bit on the news sites I decided it would be interesting to see if qBitTorrent would run on slackware 64.
So we go to the download site, copy the url, and see if Slackbuild likes it. Slackbuild leeches, untars, gives the configure options (which are a bit buggy, I know, will be fixed next release), runs configure. Configure crashes out with “blabla boost blabla”. (continue reading…)

You know what’s really annoying?

Try this:

root@Uil:/sys/devices/system/cpu/cpu0/cpufreq:0>echo ondemand > scaling_governor
root@Uil:/sys/devices/system/cpu/cpu0/cpufreq:0>dmesg
[1325843.712549] ondemand governor failed, too long transition latency of HW, fallback to performance governor


Apparently this is caused by the p4-clockmod module.
You know, this piece of junk:

Also known as “CONFIG_X86_P4_CLOCKMOD“.

The reason?
Well, the ondemand and the conservative governors want to be able to switch to a different speed before their calculations become invalid.
The p4-clockmod thing apparently makes the latency of switching so BIG that it becomes impossible. Or so they think.
Which leaves only the sucky powersave and performance governors. (and of course userspace).

The kernel menuconfig help states:

This driver should be only used in exceptional
circumstances when very low power is needed because it causes severe
slowdowns and noticeable latencies. Normally Speedstep should be used
instead.

Lovely. I’ll keep that in mind, thanks.
*enables CONFIG_X86_ACPI_CPUFREQ instead*

Note that when they’re both compiled in (as opposed to modules) the retarded thing seems to go for the clockmod. Just great.

Today, phpbb decided to fuck with me.
Or with lotjuh that is. She went to our forum, blank page.
I went there to check, works fine for me. Meh. Probably firefox fucking up as usual.
She tries lynx. Blank.
She tries telnet….

benv@janeman:~:1>telnet forum.handofhades.eu 80
Trying 80.69.76.81...
Connected to forum.handofhades.eu.
Escape character is '^]'.
GET / HTTP/1.0
Host: forum.handofhades.eu

HTTP/1.1 200 OK
Date: Tue, 01 Sep 2009 07:50:04 GMT
Server: Apache/2.2.12 (Unix) mod_ssl/2.2.12 OpenSSL/0.9.8h DAV/2 PHP/5.2.10 SVN/1.4.6
X-Powered-By: PHP/5.2.10
Content-Length: 0
Connection: close
Content-Type: text/html

Connection closed by foreign host.

What. the Fuck.

So, I check the server logs. Nothing.
NOTHING!!!!

Restarted apache. Nothing (surprise!)

Started php myself on index.php. Nothing.
Strace on php to try to figure out what the fuck.
And then I get a glimpse of where it goes wrong when I see it enter a cache dir.
The cache dir has tons of stuff, but most of them look like these:

-rw------- 1 www www 316 2009-08-23 18:42 sql_a10522de103f7e26c0338f4a3982efe0.php
-rw------- 1 www www 316 2009-08-24 21:38 sql_a12f21b584712a564d6bde0b3f733ef2.php
-rw------- 1 www www 316 2009-08-23 00:46 sql_a1386e2adab2812fb0a9076cfbb0fa1a.php
-rw------- 1 www www 316 2009-08-24 11:22 sql_a14603b084ca6516a8f591651a4f0286.php
-rw------- 1 www www 316 2009-08-24 23:02 sql_a1aaa40aaac9978cb292881202667264.php
-rw------- 1 www www 316 2009-08-24 18:23 sql_a1cb1e3ad6332900edb533b9e2a904e4.php
-rw------- 1 www www 316 2009-08-30 18:56 sql_a1cbb2008b00faafb8957bafc7082453.php
-rw------- 1 www www 316 2009-08-22 12:36 sql_a1d2e08e3641f1b8f7c03ceda2e78981.php
-rw------- 1 www www 316 2009-08-24 15:58 sql_a1eac242296c2e713f78618b8b49ad15.php

You get the point.


root@blue:/www/vhosts/forum.handofhades.eu/cache# rm sql_*.php

Fixed. Piece of cancer. Thanks for telling me…

Or more specific: CPU frequency scaling.

On my laptop this is one of the first things I enabled to make my battery last longer.
Now that we’re going to put a server in a rack where they will bill us depending on the amount of power consumed, this sounds like a welcome thing to have enabled.

Our latest Xen install has Xen 3.4, on which they’ve enabled it by default. Isn’t that nice?
So basically, if your processor etc is good enough to support it, you can mess around with it using the xenpm tool.

For instance we can check the parameters for CPU 0 like this:

root@xenbro:~# xenpm get-cpufreq-para 0
cpu id : 0
affected_cpus : *0 1 2 3
cpuinfo frequency : max [2600000] min [800000] cur [800000]
scaling_driver :
scaling_avail_gov : userspace performance powersave ondemand
current_governor : ondemand
ondemand specific :
sampling_rate : max [10000000] min [10000] cur [20000]
up_threshold : 80
scaling_avail_freq : 2600000 1900000 1400000 *800000
scaling frequency : max [2600000] min [800000] cur [800000]

As you can see, it’s very much like the whole cpufreq ordeal. It has an ondemand governor, a powersave one, etc. Right now this CPU is using the ondemand governor, which will ramp up the clock when demand increases.
However, since this is a quad core and not a real quad processor machine we can only change the governor for all 4 cores at the same time, not for individual ones. (would be cool to have 1 core burning away power while the rest idles by….).

Anyway, the xenpm tool allows us to monitor and change various aspects of this.
For instance this will do a little benchmark and show the processor states during the benchmark.

root@xenbro:~# xenpm start 10
Timeout set to 10 seconds
Start sampling, waiting for CTRL-C or SIGINT or SIGALARM signal ...
Elapsed time (ms): 10003

CPU0: Residency(ms) Avg Res(ms)
C0 49 ( 0.50%) 0.04
C1 9953 (99.50%) 7.19

Avg freq 800000 KHz

CPU1: Residency(ms) Avg Res(ms)
C0 13 ( 0.14%) 0.07
C1 9989 (99.86%) 48.49

Avg freq 800000 KHz

CPU2: Residency(ms) Avg Res(ms)
C0 83 ( 0.83%) 0.21
C1 9919 (99.17%) 25.05

Avg freq 800000 KHz

CPU3: Residency(ms) Avg Res(ms)
C0 28 ( 0.28%) 0.10
C1 9973 (99.72%) 33.92

Avg freq 800000 KHz

As you can see my processor is mostly idle.
State C0 is the most active state, C1 is sleeping with use of the HLT instruction.
Your processor can have many more states, like my laptop which has 4.

Anyway, I put the change to ondemand governor in my /etc/rc.d/rc.local, so let’s hope it helps.

To read some more about the details of this stuff you can check out the Xenpm wiki page.

So I’m working on a little info script (check out Infoscreen) so I can have a nice overview
of my server when I look at console number one without having to log in etc.

Simple question:
“Where in /proc can I find a list of IP addresses with corresponding interfaces?”

Simple answer:
Try /proc/net/if_inet6!

wouter@wouter-laptop:~:0>cat /proc/net/if_inet6
00000000000000000000000000000001 01 80 10 80 lo
20010888148d0000022100fffe221352 04 40 00 00 wlan1
fe80000000000000022100fffe221352 04 40 20 80 wlan1

… that’s great…. but I really wanted the IPv4 addresses as well.
“/proc/net/if_inet4” or “/proc/net/if_inet”? Noooooo….

Conclusion: KANKER LINUX!

Obviously I can get the address by calling ‘ip addr show‘, ‘ifconfig‘ or a heap of other solution involving calling ioctl on sockets or using the netlink interface… but seriously, blegh.

The most retarded thing is that pretty much every other statistic about my network devices is there… including active connections and whatnot, but ipv4 addresses? Nooooo….. *RAAH*

Another day, another time for fun!

Since we got Xen up and running yesterday, it’s now time for actually having some fun with it.
The goals are:

1. Getting xend started automagically when booting without destroying my network connection
2. Getting a domU up and running with a network connection
3. Getting an internal network between the domUs and dom0, shielded from the big bad internet.

(continue reading…)