Category Archives: Ubuntu 8.10

Freeing up RAM in Linux

NOTE: Little clarification, this is not needed at all ,as memory is freed when required.

WHY IT MAY BE HELP-FULL: This clears the page-cache , dentires and inodes.

IT’S TRANSLATION : It may be that you are watching a movie or using a Virtual Machine , a resource hungry process has filled up your ram by caching data and the data needs to be continuously removed  to make space for new data . This is managed by the kernel.

IF YOU STILL DON’T  GET IT: Notice  video in your movie hanging (not audio) while your ram gets cached Or your system running a bit slow ?


1) Stop the process consuming loads of memory. (Check System Monitor).
2) Open a terminal with root privileges .
3) Sync
4) echo 3 > /proc/sys/vm/drop_caches
5) echo 0 > /proc/sys/vm/drop_caches

Reliance ATZ USB CDMA Modem on fedora , ubuntu and other linux

1) Find Vendor and ProdID

Do

cat /proc/bus/usb/devices

In the generated list where Manufacturer is ZTE , Incorporated

Take Vendor and ProdID

eg. Vendor=19d2 ProdID=fffd

-You can also use lsusb to get entry with ONDA Communication S.p.A in format   a:b

eg  19d2:fffd

2) Load Module
modprobe usbserial vendor=0x19d2 product=0xfffd

After this step 3 interfaces /dev/ttyUSB* where *(0-2)
should be created .(if not then rmmod usbserial ->remove device->modprobe again->insert device )

3)Configure (Run in root mode)(NOT FOR FEDORA go to 6)
wvdialconf

4)Edit /etc/wvdial.conf
Add number eg. #777
Add your username and password in the fields.

5)Run
Ideally running wvdial should be enough.
(try ping google.com to check if you are connected)

6)However in fedora(and if above steps dont work for you) after modprobe
Go to System>Administration>Network>New>Modem>
In Modem Properties (Despite error)
change device to /dev/ttyUSB0
Modem Volume=low
->Forward
Phone number #777
Username and Password -as you have
Provider Name -any
->Forward
Save And activate
Try ping google.com

Running Wifi on Ubuntu 8.10 (HP 6515b)

Intrepid Ibex comes with the Broadcom STA driver which has wl.ko module but ssb and b43 modules r loaded..

Add folowing lines to /etc/modprobe.d/blacklist

blacklist ssb

blacklist b43

Reboot and check if your wifi is working or not .

If not (and the modules still got loaded into memory)

delete following modules

/lib/modules/’uname -r ‘/kernel/drivers/ssb/ssb.ko

and

/lib/modules/’uname -r ‘/kernel/drivers/net/wireless/b43/b43.ko