Posts Tagged ‘linux’
Make DVD ISO image from VIDEO_TS folder
Here is a quick shell script to use on Mac OS X to make a DVD iso from a VIDEO_TS folder. Save is as “mkdvdiso” and just specify the folder containing the VIDEO_TS folder, not the VIDEO_TS folder itself. You can also override the DVD name and choose between hdiutil (Mac OS X command line utility that uses the DiskImages framework) or mkisofs from the cdrtools package (I used macports to install cdrtools on my OS X 10.6 system).
#!/bin/bash
#
# THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
# OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
# IN NO EVENT SHALL NORMAN WALSH OR ANY OTHER CONTRIBUTOR BE LIABLE FOR
# ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
# TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
# SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
#
usehdiutil=1
usemkisofs=0
dvdname=""
while [ ${#} -gt 0 ]; do
case "${1}" in
-h|--hdiutil)
usehdiutil=1
usemkisofs=0
shift
;;
-m|--mkisofs)
usemkisofs=1
usehdiutil=0
shift
;;
-n|--dvd-name)
dvdname="${2}"
shift 2
;;
*)
dvddir="${1}"
shift
;;
esac
done
if [ -z "${dvdname}" ]; then
dvdname="$(basename "${dvddir}")"
fi
echo -n "Making DVD ISO for ${dvdname} using "
[ ${usehdiutil} -eq 1 ] && echo "hdiutil"
[ ${usemkisofs} -eq 1 ] && echo "mkisofs"
if [ ${usehdiutil} -eq 1 ]; then
hdiutil makehybrid -iso -joliet -udf -udf-version 1.02 -default-volume-name "${dvdname}" -o "${dvdname}.iso" "${dvddir}"
fi
if [ ${usemkisofs} -eq 1 ]; then
mkisofs -f -dvd-video -udf -V "${dvdname}" -o "${dvdname}.iso" "${dvddir}"
fi
Example Usage
mkdvdiso /Volumes/Fry/DVD_VIDEO
will make a image called DVD_IMAGE.iso in the current directory.
mkdvdiso -m -n MY_DVD /Volumes/Fry/DVD_VIDEO
will make a image called MY_DVD.iso in the current directory using mkisofs.
DD-WRT: Overclocking Linksys WRT610N v2 Router
To overclock your Linksys WRT610Nv2 using DD-WRT is relatively easy. You need can either run the commands in the Administration > Commands interface in the web GUI or on the command line through telnet or SSH. The WRT610Nv2 comes default clocked at 480MHz, but it can be pumped as high as 532MHz. Keep in mind going above 532MHz seems to cause the device to actual perform at a lower clock rate. Why do such a thing? After overclocking, I’ve seen a 2-3MB/s increase in my Samba file transfers, which is a warm welcome, since file transfers on these home routers is relatively poor due to the lightweight hardware these devices have.
Warning: overclocking may brick your device, overheat, or due other such things that cause it to permanently break. Proceed at your own risk.
To overclock just run the following commands
nvram set clkfreq="532,266,133" nvram commit reboot
To change it back to the factory defaults, just run
nvram set clkfreq="480,240,120" nvram commit reboot
Original Reference: Safe overclocking ‘speeds’ for WRT610N v2
DD-WRT: Shutdown script using Optware the Right Way
Ever want to shutdown your home router running DD-WRT with Optware the Right Way and correctly unmount any USB drives. Well DD-WRT doesn’t have a halt or a shutdown command, only reboot, but you could easily put the router a state that is safe to just pull-the-plug. Just create a shutdown script, say called /opt/local/bin/shutdown and put the following inside:
#!/bin/sh /opt/etc/init.d/optK
Then make the script executable my changing the permissions.
chmod 755 /opt/local/bin/shutdown
Now as long as /opt/local/bin is in your current path, you can just type shutdown to cause Optware to initiate its shutdown sequence. When it finishes, you can simply power down the router without worry about your filesystems on your external disks.
Bandwidth Shaping with Linux
This howto is for restricting raw bandwidth on network interfaces using Linux 2.6. The specific example presented here is run on a Linksys WRT610Nv2 home router running DD-WRT (build r14144)
On the router, the device, br0 is the bridged device that is in the internet side of things. We will use that device for shaping our internet traffic in and out of the router. I am using my home internet connection, which is Cox cable internet with 12Mbps download and 2Mbps upload or 12288 kilobits per second and 2048 kilobits per second, respectively.
First, lets setup some bash variables to point to the various commands we will use throughout the script. We will also set variables to indicate our maximum bandwidth in both directions.
TC="/usr/sbin/tc" IPT="/usr/sbin/iptables" IP="/usr/sbin/ip" INSMOD="/sbin/insmod" RMMOD="/sbin/rmmod" DNLD_BANDWIDTH="12288kbit" UPLD_BANDWIDTH="2048kbit"
Next, lets setup the download shaping by adding a queuing discipline (qdisc) to device br0 and tell the qdisc the maximum throughput.
TCA="${TC} class add dev br0"
TFA="${TC} filter add dev br0"
TQA="${TC} qdisc add dev br0"
${TQA} root handle 1: htb
${TCA} parent 1: classid 1:1 htb rate ${DNLD_BANDWIDTH}
Next, we are going to setup 2 classes. Each class will be setup with a guaranteed bandwidth and a maximum bandwidth if the other class is underutilized. The first class will have a guaranteed download bandwidth of 8Mbps. The second class will have a guaranteed download bandwidth of 4Mbps. Both classes will be able to utilize up to 12Mbps depending on how active the other class is.
{TCA} parent 1:1 classid 1:10 htb rate 8192kbit ceil ${DNLD_BANDWIDTH} prio 1
{TCA} parent 1:1 classid 1:11 htb rate 4096kbit ceil ${DNLD_BANDWIDTH} prio 2
{TQA} parent 1:10 handle 10: sfq perturb 10
{TQA} parent 1:11 handle 11: sfq perturb 10
Now we need to setup a filter for each class. This is ensure only packets marked with the filter’s tag will be restricted. The mark is denoted by the ip handle. Here we will use 10 and 11, to match the classids of the classes we just defined.
${TFA} parent 1:0 prio 2 protocol ip handle 10 fw flowid 1:10
${TFA} parent 1:0 prio 2 protocol ip handle 11 fw flowid 1:11
Now to setup the upload shaping, we have to create a imq device.
${INSMOD} imq
${INSMOD} ipt_IMQ
${IP} link set imq0 up
Next, we need to setup a qdisc, classes, and filters for our 2 classes. Just like we did for download, only this time using the imq0 device and the upload bandwidths. The first class will have a guaranteed upload bandwidth of ~1.3Mbps and the second class will have a guaranteed upload bandwidth of 700Kbps.
TCAU="${TC} class add dev imq0"
TFAU="${TC} filter add dev imq0"
TQAU="${TC} qdisc add dev imq0"
${TQAU} root handle 1: htb
${TCAU} parent 1: classid 1:1 htb rate ${UPLD_BANDWIDTH}
${TCAU} parent 1:1 classid 1:10 htb rate 1348kbit ceil ${UPLD_BANDWIDTH} prio 1
${TCAU} parent 1:1 classid 1:11 htb rate 700kbit ceil ${UPLD_BANDWIDTH} prio 2
${TQAU} parent 1:10 handle 10: sfq perturb 10
${TQAU} parent 1:11 handle 11: sfq perturb 10
${TFAU} parent 1:0 prio 2 protocol ip handle 10 fw flowid 1:10
${TFAU} parent 1:0 prio 2 protocol ip handle 11 fw flowid 1:11
Finally, now that all our shaping is setup, we need to use iptables to mark packets to indicate which packets to shape. My internal network is 192.168.1.0/24. So we only mark packets headed for the internet and leave internal traffic alone. The first class will be restricted to a single IP address. The second class will be restrict to a group of IPs using CIDR notation (32 DHCP addresses from the router).
# download
${IPT} -t mangle -A POSTROUTING -s ! 192.168.1.0/24 -d 192.168.1.2 -j MARK --set-mark 10
${IPT} -t mangle -A POSTROUTING -s ! 192.168.1.0/24 -d 192.168.1.128/27 -j MARK --set-mark 11
# upload
${IPT} -t mangle -A PREROUTING -j IMQ --todev 0
${IPT} -t mangle -A PREROUTING -d ! 192.168.1.0/24 -s 192.168.1.2 -j MARK --set-mark 10
${IPT} -t mangle -A PREROUTING -d ! 192.168.1.0/24 -s 192.168.1.128/27 -j MARK --set-mark 11
Note: I would really like to use iptables range of address notation (e.g. -m iprange –src-range 192.168.1.3-192.168.1.254), but current builds of DD-WRT do not seem to work with that notation. I posted to the DD-WRT forums and I’ll I got was IP ranges are not supported. So for my own purposes, I just have giant script with many iptables commands, one for each IP address I want to shape.
To make it easy to start, stop, restart, I wrote an init.d style script for the above. I use it as part of the DD-WRT custom firewall script.
#!/bin/bash
TC="/usr/sbin/tc"
IPT="/usr/sbin/iptables"
IP="/usr/sbin/ip"
INSMOD="/sbin/insmod"
RMMOD="/sbin/rmmod"
DNLD_BANDWIDTH="12228kbit"
UPLD_BANDWIDTH="2048kbit"
DNLD_CLASS10_BANDWIDTH="8192kbit"
DNLD_CLASS11_BANDWIDTH="4096kbit"
UPLD_CLASS10_BANDWIDTH="1348kbit"
UPLD_CLASS11_BANDWIDTH="700kbit"
[ -x ${TC} ] || exit 1
[ -x ${IPT} ] || exit 1
[ -x ${IP} ] || exit 1
[ -x ${INSMOD} ] || exit 1
[ -x ${RMMOD} ] || exit 1
case "${1}" in
start)
echo -n "Starting bandwidth shaping service ... "
# download
TCA="${TC} class add dev br0"
TFA="${TC} filter add dev br0"
TQA="${TC} qdisc add dev br0"
${TQA} root handle 1: htb
${TCA} parent 1: classid 1:1 htb rate ${DNLD_BANDWIDTH}
${TCA} parent 1:1 classid 1:10 htb rate ${DNLD_CLASS10_BANDWIDTH} ceil ${DNLD_BANDWIDTH} prio 1
${TCA} parent 1:1 classid 1:11 htb rate ${DNLD_CLASS11_BANDWIDTH} ceil ${DNLD_BANDWIDTH} prio 2
${TQA} parent 1:10 handle 10: sfq perturb 10
${TQA} parent 1:11 handle 11: sfq perturb 10
${TFA} parent 1:0 prio 2 protocol ip handle 10 fw flowid 1:10
${TFA} parent 1:0 prio 2 protocol ip handle 11 fw flowid 1:11
# upload
${INSMOD} imq
${INSMOD} ipt_IMQ
${IP} link set imq0 up
TCAU="${TC} class add dev imq0"
TFAU="${TC} filter add dev imq0"
TQAU="${TC} qdisc add dev imq0"
${TQAU} root handle 1: htb
${TCAU} parent 1: classid 1:1 htb rate ${UPLD_BANDWIDTH}
${TCAU} parent 1:1 classid 1:10 htb rate ${UPLD_CLASS10_BANDWIDTH} ceil ${UPLD_BANDWIDTH} prio 1
${TCAU} parent 1:1 classid 1:11 htb rate ${UPLD_CLASS11_BANDWIDTH} ceil ${UPLD_BANDWIDTH} prio 2
${TQAU} parent 1:10 handle 10: sfq perturb 10
${TQAU} parent 1:11 handle 11: sfq perturb 10
${TFAU} parent 1:0 prio 2 protocol ip handle 10 fw flowid 1:10
${TFAU} parent 1:0 prio 2 protocol ip handle 11 fw flowid 1:11
# download
${IPT} -t mangle -A POSTROUTING -s ! 192.168.1.0/24 -d 192.168.1.2 -j MARK --set-mark 10
${IPT} -t mangle -A POSTROUTING -s ! 192.168.1.0/24 -d 192.168.1.128/27 -j MARK --set-mark 11
# upload
${IPT} -t mangle -A PREROUTING -j IMQ --todev 0
${IPT} -t mangle -A PREROUTING -d ! 192.168.1.0/24 -s 192.168.1.2 -j MARK --set-mark 10
${IPT} -t mangle -A PREROUTING -d ! 192.168.1.0/24 -s 192.168.1.128/27 -j MARK --set-mark 11
echo "done"
;;
stop)
echo -n "Stopping bandwidth shaping service ... "
# download
${IPT} -t mangle -D POSTROUTING -s ! 192.168.1.0/24 -d 192.168.1.2 -j MARK --set-mark 10
${IPT} -t mangle -D POSTROUTING -s ! 192.168.1.0/24 -d 192.168.1.128/27 -j MARK --set-mark 11
# upload
${IPT} -t mangle -D PREROUTING -d ! 192.168.1.0/24 -s 192.168.1.2 -j MARK --set-mark 10
${IPT} -t mangle -D PREROUTING -d ! 192.168.1.0/24 -s 192.168.1.128/27 -j MARK --set-mark 11
${IPT} -t mangle -D PREROUTING -j IMQ --todev 0
${TC} qdisc del dev br0 root
${TC} qdisc del dev imq0 root
${IP} link set imq0 down
${RMMOD} ipt_IMQ
${RMMOD} imq
echo "done"
;;
restart)
${0} stop
sleep 1
${0} start
;;
status)
${TC} qdisc show dev br0
${TC} class show dev br0
${TC} filter show dev br0
${TC} qdisc show dev imq0
${TC} class show dev imq0
${TC} filter show dev imq0
;;
*)
echo "Usage: ${0} {start|stop|restart|status}"
exit 1
;;
esac
exit 0
Resource Based Scheduler
RBS PDF
Abstract
This paper describes the Resource Based Scheduler (RBS), a modification of the Linux 2.6 kernel scheduler. RBS provides an optimized scheduler which makes more intelligent scheduling decisions based on the current resource needs of the processes to be scheduled. We report on the design of RBS and the lessons we have learned by implementing a subset of its design.
Authors
Joe Roback
Marshall McMullen
Jose W Gifford