Hi there.

I'm rather new to Linux, been a MS engineer all my life.
Have tried Debian (simple), Suse (irritating), Ubuntu (for kids) and settled on Fedora. tried 6, it was OK-ish

Currently running Fedora7 (2.6.22.4-65) on:

Gigabyte 965-gs3 board with an unlocked Intel dual core 3.4Ghz running at 4.1Ghz (super cooled)
2 GIG 667 RAM
250 GIG IDE (Fedora)
160 SATA - windows xp64 (automounted)
160 SATA - Windows xpsp2 & enterprise (automounted)
HP DVD RW
Nvidia PCIE 6800GT-256
Acer 23" LCD @ 1400x1050

Under F7 everything works fine (Beryl, Firefox, Nessus, Etherape, snort & crack, Skype, GoodleEarth, OpenOffice, Gimp, CD-DVD burning, Stellarium, Amarok) (all screaming fast) but as-of (last week?) things seem to slow-down only when connected to the web.

I had some issues getting the correct Nvidia driver for Beryl but that's sorted.


At first I thought it was CUPS, so I disabled the service, same thing.
Then I thought perhaps it's the CPU scaling, disabled that, same thing still.

Switch off the DHL router and things are back to speed. (apps start immediately)
Switch on the DHL router and certain apps (not all) take forever to start or do not start at all.

Even Firefox takes about 8 seconds to start (compared to 1-2 normally).

I even went back to running at 3.4Ghz but the problem remains.
Whenever the network is connected, the machine slows down.

Some applications sometimes do not start at all. Says (Starting Terminal or Thunderbird etc) but the app never starts. I have to click the icon again or run the command again.. etc etc.

When running at 4Ghz under XP64 all seems fine so it's not the hardware. all sensors indicate happiness.


Under F7 once I switch off the DHL modem or disable the network service the machine runs at normal speed.


Any help will be appreciated..
This is INCREDIBLY annoying.




Logs below: pls let me know what else would be of help...!


FSTAB

# /etc/fstab: static file system information.
#
# <file system> <mount point> <type> <options> <dump> <pass>

tmpfs /dev/shm tmpfs defaults 0 0
devpts /dev/pts devpts gid=5,mode=620 0 0
sysfs /sys sysfs defaults 0 0
proc /proc proc defaults 0 0
#Entry for /dev/mapper/VolGroup01-LogVol00 :
LABEL=/ / ext3 defaults 1 1
/dev/sda1 /boot ext3 defaults 1 2
/dev/sdc1 /media/xp64 ntfs defaults,locale=en_US.UTF-8,rw 0 0
/dev/sdb1 /media/xp ntfs defaults,locale=en_US.UTF-8,rw 0 0
/dev/VolGroup01/LogVol01 swap swap defaults 0 0



xorg.conf

Section "Files"
ModulePath "/usr/lib/xorg/modules/extensions/nvidia"
ModulePath "/usr/lib/xorg/modules"
EndSection

Section "ServerFlags"
Option "AIGLX" "on"
EndSection

Section "InputDevice"
Identifier "Keyboard0"
Driver "kbd"
Option "XkbModel" "pc105"
Option "XkbLayout" "us"
EndSection

Section "Monitor"
Identifier "Monitor0"
ModelName "Monitor 1400x1050"
HorizSync 31.5 - 90.0
VertRefresh 50.0 - 90.0
Option "dpms"
EndSection

Section "Device"
Identifier "Videocard0"
Driver "nvidia"
Option "AddARGBGLXVisuals" "True"
EndSection

Section "Screen"
Identifier "Screen0"
Device "Videocard0"
Monitor "Monitor0"
DefaultDepth 24
SubSection "Display"
Viewport 0 0
Depth 24
EndSubSection
EndSection

Section "Extensions"
Option "Composite" "Enable"
EndSection

cat /etc/resolv.conf

See if it changes when the DSL is on/off.

What is the hostname? What happens when you 'dig $(hostname)' when the DSL is on or off?

Hi Dgar,
Thanks for the reply...


[root@moonshine ~]# dig $(hostname)

; <<>> DiG 9.4.2b1 <<>> moonshine.localhost
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 35566
;; flags: qr rd; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 0
;; WARNING: recursion requested but not available

;; QUESTION SECTION:
;moonshine.localhost. IN A

;; Query time: 4180 msec
;; SERVER: 10.0.0.2#53(10.0.0.2)
;; WHEN: Tue Sep 11 17:31:19 2007
;; MSG SIZE rcvd: 37




as for 'cat /etc/resolv.conf'.

The DNS server stays the same 10.0.0.2
No change there.

Dgar,

Thanks a million for your input.
It was a DNS issue after all.


It seems my DHL router decided to stop handing over DNS server addresses to my machine upon DHCP discover.

Instead of handing over teh DNS server addresses it hands over its own address.
Default gateway and DNS was all the same address.

Each time my machine requests name resolution the router sits with the request for while (couple of seconds) before handing it over to the DNS server at the ISP.

Very weird that it still works under Windows though. Obviously the router is optimized for Microsoft DNS. It's an off the helf item from the telco.

My only guess is something is up? with BIND on my Fedora config or the DHL router's firmware is a bit iffy.

I contacted the ISP and asked for their DNS addresses, added them manually and now all seems to be happy.
4ghz machine again performing like it should.

greets
Henpen.

Windows runs a caching nameserver itself, so the machine was finding commonly repeated name lookups answered instantly. You can install ncsd and get the same effect.