[[PageOutline]]

= 2008-11-16 =

== Event: SC'08 ==
 * SC'08
   * 13:00-13:30: Cloud Computing and Grid Computing 360-Degree Compared - GCE08 @ Room 11AB.
 * [http://www.weather.com/weather/tenday/USTX0057?from=36hr_fcst10DayLink_undeclared Austin 近十日天氣預報]
 * 展場無線網路測試:
{{{
C:\>tracert 140.110.1.1

Tracing route to 140.110.1.1 over a maximum of 30 hops

  1     2 ms    <1 ms    <1 ms  conf-rtr-south-vlan203.sc08.org [140.221.224.3]
  2     3 ms     1 ms     1 ms  core-rtr-1-conf-rtr-south.sc08.org [140.221.251.114]
  3    34 ms    33 ms    33 ms  nlr-la-rtr-core-rtr-1.sc08.org [140.221.251.134]
  4    60 ms    58 ms    59 ms  seat-losa-49.layer3.nlr.net [216.24.186.13]
  5    62 ms    60 ms    64 ms  twaren-1-is-jmb-776.lsanca.pacificwave.net [207.231.241.133]
  6   294 ms   313 ms   313 ms  la-76-hc-gsr.twaren.net [211.79.48.229]
  7   250 ms   313 ms   312 ms  hc-76-v20.twaren.net [211.79.60.113]
  8   248 ms   313 ms   313 ms  140.110.1.1

Trace complete.
                             My traceroute  [v0.73]
intrepid (0.0.0.0)                                     Sun Nov 16 00:54:03 2008
Keys:  Help   Display mode   Restart statistics   Order of fields   quit
                                       Packets               Pings
 Host                                Loss%   Snt   Last   Avg  Best  Wrst StDev
 1. 172.21.253.2                      0.0%   259    0.3   0.3   0.2   6.1   0.4
 2. 140.110.1.1                       0.0%   259  226.3 279.1 221.1 1018.  61.5

jazz@intrepid:~$ sudo iperf -c 140.110.240.192 -u
------------------------------------------------------------
Client connecting to 140.110.240.192, UDP port 5001
Sending 1470 byte datagrams
UDP buffer size:   122 KByte (default)
------------------------------------------------------------
[  3] local 172.21.253.152 port 33083 connected with 140.110.240.192 port 5001
[ ID] Interval       Transfer     Bandwidth
[  3]  0.0-10.0 sec  1.25 MBytes  1.05 Mbits/sec
[  3] Sent 892 datagrams
[  3] Server Report:
[ ID] Interval       Transfer     Bandwidth       Jitter   Lost/Total Datagrams
[  3]  0.0- 9.9 sec  1.25 MBytes  1.05 Mbits/sec  2.526 ms    0/  891 (0%)
[  3]  0.0- 9.9 sec  1 datagrams received out-of-order

jazz@intrepid:~$ sudo iperf -c 140.110.240.192 -u -w 10M
------------------------------------------------------------
Client connecting to 140.110.240.192, UDP port 5001
Sending 1470 byte datagrams
UDP buffer size:   244 KByte (WARNING: requested 10.0 MByte)
------------------------------------------------------------
[  3] local 172.21.253.152 port 56643 connected with 140.110.240.192 port 5001
[ ID] Interval       Transfer     Bandwidth
[  3]  0.0-10.0 sec  1.25 MBytes  1.05 Mbits/sec
[  3] Sent 893 datagrams
[  3] Server Report:
[ ID] Interval       Transfer     Bandwidth       Jitter   Lost/Total Datagrams
[  3]  0.0-10.0 sec  1.25 MBytes  1.05 Mbits/sec  0.670 ms    0/  893 (0%)
}}}
 * 展場光纖網路測試:
{{{
C:\>tracert 140.110.1.1

Tracing route to 140.110.1.1 over a maximum of 30 hops

  1    <1 ms    <1 ms    <1 ms  A-rtr.1851.sc08.org [140.221.141.1]
  2    32 ms     1 ms    <1 ms  core-rtr-1-2-dnoc-rtr-2046-2.sc08.org [140.221.251.69]
  3    32 ms    32 ms    32 ms  nlr-la-rtr-core-rtr-1.sc08.org [140.221.251.134]
  4    58 ms    57 ms    57 ms  seat-losa-49.layer3.nlr.net [216.24.186.13]
  5    60 ms    59 ms    59 ms  twaren-1-is-jmb-776.lsanca.pacificwave.net [207.231.241.133]
  6   224 ms   225 ms   224 ms  la-76-tp-gsr.twaren.net [211.79.48.209]
  7   226 ms   226 ms   226 ms  hc-76-v20.twaren.net [211.79.60.113]
  8   227 ms   227 ms   227 ms  140.110.1.1

Trace complete.

jazz@intrepid:~$ sudo mtr 140.110.1.1

                             My traceroute  [v0.73]
intrepid (0.0.0.0)                                     Sun Nov 16 00:44:24 2008
Resolver: Received error response 5. (refused by name server)elds   quit
                                       Packets               Pings
 Host                                Loss%   Snt   Last   Avg  Best  Wrst StDev
 1. 172.21.253.2                      0.0%   616    0.3   0.2   0.2   1.3   0.1
 2. 140.110.1.1                       0.0%   616  228.1 228.9 227.6 410.2  12.3

jazz@intrepid:~$ sudo iperf -c 140.110.240.192 -u
------------------------------------------------------------
Client connecting to 140.110.240.192, UDP port 5001
Sending 1470 byte datagrams
UDP buffer size:   122 KByte (default)
------------------------------------------------------------
[  3] local 172.21.253.152 port 50095 connected with 140.110.240.192 port 5001
[ ID] Interval       Transfer     Bandwidth
[  3]  0.0-10.0 sec  1.25 MBytes  1.05 Mbits/sec
[  3] Sent 893 datagrams
[  3] Server Report:
[ ID] Interval       Transfer     Bandwidth       Jitter   Lost/Total Datagrams
[  3]  0.0-10.0 sec  1.25 MBytes  1.05 Mbits/sec  1.975 ms    0/  892 (0%)
[  3]  0.0-10.0 sec  1 datagrams received out-of-order

jazz@intrepid:~$ sudo iperf -c 140.110.240.192 -u -w 10M
------------------------------------------------------------
Client connecting to 140.110.240.192, UDP port 5001
Sending 1470 byte datagrams
UDP buffer size:   244 KByte (WARNING: requested 10.0 MByte)
------------------------------------------------------------
[  3] local 172.21.253.152 port 53022 connected with 140.110.240.192 port 5001
[ ID] Interval       Transfer     Bandwidth
[  3]  0.0-10.0 sec  1.25 MBytes  1.05 Mbits/sec
[  3] Sent 893 datagrams
[  3] Server Report:
[ ID] Interval       Transfer     Bandwidth       Jitter   Lost/Total Datagrams
[  3]  0.0-10.0 sec  1.25 MBytes  1.05 Mbits/sec  1.827 ms    0/  893 (0%)
}}}

== BUGFIX: jfbterm ==

 * [DRBL] jfbterm Bug
   * https://bugs.launchpad.net/ubuntu/+source/jfbterm/+bug/253163
   * http://launchpadlibrarian.net/16414131/jfbterm-segfault.txt
   * http://launchpadlibrarian.net/16414135/jfbterm-segfault-strace.txt
   * [測試]
     * 安裝 [http://ftp.twaren.net/Linux/Ubuntu/ubuntu-cd/8.10/ubuntu-8.10-server-amd64.iso Ubuntu 8.10 Server AMD64]
     * 
{{{
root@intrepid:~# apt-get update
root@intrepid:~# apt-get upgrade
root@intrepid:~# reboot
root@intrepid:~# uname -a
Linux intrepid 2.6.27-7-server #1 SMP Tue Nov 4 20:16:57 UTC 2008 x86_64 GNU/Linux
root@intrepid:~# apt-get install jfbterm v86d
root@intrepid:~# reboot
root@intrepid:~# dpkg -S chvt
kbd: /usr/share/man/man1/chvt.1.gz
kbd: /bin/chvt
root@intrepid:~# chvt 1
root@intrepid:~# rmmod uvesafb
ERROR: Module uvesafb does not exist in /proc/modules
root@intrepid:~# modprobe uvesafb mode_option=1024x768
root@intrepid:~# screen
root@intrepid:~# jfbterm -e ls
... 略 ...
color 15 : ffff, ffff
cannot mmap(mmio) : Invalid argument
Segmentation fault
}}}
 * [備註] 如果沒有裝 v86d 的話，當執行 modprobe uvesafb 時會在 dmesg 看到以下資訊
{{{
[  703.839376] uvesafb: failed to execute /sbin/v86d
[  703.840224] uvesafb: make sure that the v86d helper is installed and executable
[  703.841494] uvesafb: Getting VBE info block failed (eax=0x4f00, err=-2)
[  703.842307] uvesafb: vbe_init() failed with -22
[  703.843019] uvesafb: probe of uvesafb.0 failed with error -22
}}}
 * [備註] 如果有裝 v86d 的話，當執行 modprobe uvesafb 時會在 dmesg 看到以下資訊
{{{
[  268.848377] uvesafb: VMware, IncVMware virtual machine2.0, VMware virtual machine2.0, 2.0, OEM: V M ware, Inc. VBE support 2.0VMware, IncVMware virtual machine2.0, VBE v2.0
[  268.884099] uvesafb: no monitor limits have been set, default refresh rate will be used
[  268.885202] uvesafb: VBE state buffer size cannot be determined (eax=0x0, err=0)
[  268.885265] uvesafb: scrolling: redraw
[  268.896617] mtrr: your processor doesn't support write-combining
[  268.909303] Console: switching to colour frame buffer device 128x48
[  269.938085] uvesafb: framebuffer at 0xf0000000, mapped to 0xffffc20000180000, using 16384k, total 16384k
[  269.938101] fb0: VESA VGA frame buffer device
}}}
 * 
{{{
root@intrepid:~# modinfo uvesafb
filename:       /lib/modules/2.6.27-7-server/kernel/drivers/video/uvesafb.ko
description:    Framebuffer driver for VBE2.0+ compliant graphics boards
author:         Michal Januszewski <spock@gentoo.org>
license:        GPL
srcversion:     21EDEFDED06E0673208A0D5
depends:
vermagic:       2.6.27-7-server SMP mod_unload modversions
parm:           scroll:Scrolling mode, set to 'redraw', 'ypan', or 'ywrap' (scroll)
parm:           vgapal:Set palette using VGA registers (invbool)
parm:           pmipal:Set palette using PMI calls (bool)
parm:           mtrr:Memory Type Range Registers setting. Use 0 to disable. (uint)
parm:           blank:Enable hardware blanking (bool)
parm:           nocrtc:Ignore CRTC timings when setting modes (bool)
parm:           noedid:Ignore EDID-provided monitor limits when setting modes (bool)
parm:           vram_remap:Set amount of video memory to be used [MiB] (uint)
parm:           vram_total:Set total amount of video memoery [MiB] (uint)
parm:           maxclk:Maximum pixelclock [MHz], overrides EDID data (ushort)
parm:           maxhf:Maximum horizontal frequency [kHz], overrides EDID data (ushort)
parm:           maxvf:Maximum vertical frequency [Hz], overrides EDID data (ushort)
parm:           mode_option:Specify initial video mode as "<xres>x<yres>[-<bpp>][@<refresh>]" (charp)
parm:           vbemode:VBE mode number to set, overrides the 'mode' option (ushort)
parm:           v86d:Path to the v86d userspace helper. (string)

root@intrepid:~# LANG=C apt-cache policy v86d
v86d:
  Installed: 0.1.5-1ubuntu2
  Candidate: 0.1.5-1ubuntu2
  Version table:
 *** 0.1.5-1ubuntu2 0
        500 http://tw.archive.ubuntu.com intrepid/universe Packages
        100 /var/lib/dpkg/status

root@intrepid:~# LANG=C apt-cache policy jfbterm
jfbterm:
  Installed: 0.4.7-7.2
  Candidate: 0.4.7-7.2
  Version table:
 *** 0.4.7-7.2 0
        500 http://tw.archive.ubuntu.com intrepid/universe Packages
        100 /var/lib/dpkg/status
}}}
 * 追蹤 jfbterm 的 deb package 原始碼
{{{
root@intrepid:~# apt-get build-dep jfbterm
root@intrepid:~# apt-get install dpkg-dev
root@intrepid:~# apt-get source jfbterm
}}}
 * uvesafb 作者的推測:
{{{
As to why the console becomes unresponsive after exiting jfbterm --
jfbterm sets KD_GRAPHICS mode on the console on which it is started,
and apparently fails to set it back to KD_TEXT before segfaulting.  This
leaves the console in the broken state.
}}}
 * 尋找合理懷疑對象:
{{{
root@intrepid:~/jfbterm-0.4.7# grep "KD_GRAPHICS" *
vterm.c:        ioctl(0, KDSETMODE, KD_GRAPHICS);

root@intrepid:~/jfbterm-0.4.7# grep "KD_TEXT" *
main.c:        if (mode == KD_TEXT) {
vterm.c:        ioctl(0, KDSETMODE, KD_TEXT);
}}}