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**IgnorantGuru** · Nov 01, 2009, 05:06 PM

Re: A Collection of Karmic Tips and Tricks

Here is the vnc4server setup script as an attachment. The version in the original post above
had the server-args line broken up because it made the post too wide.

Attached Files

vnc4server-setup.txt (1.5 KB, 10 views)

**Snowhog** · Nov 01, 2009, 05:07 PM

Re: A Collection of Karmic Tips and Tricks

So much better. Thank you.

**dibl** · Nov 01, 2009, 05:18 PM

Re: A Collection of Karmic Tips and Tricks

Good stuff -- thanks for contributing!

**Qqmike** · Nov 01, 2009, 05:21 PM

Re: A Collection of Karmic Tips and Tricks

Suggest a TOC?

Just a basic Table of Contents so a reader
can quickly scan it to see if his problem is there.

**IgnorantGuru** · Nov 01, 2009, 05:48 PM

Re: A Collection of Karmic Tips and Tricks

Originally posted by Qqmike

Suggest a TOC?

Just a basic Table of Contents so a reader
can quickly scan it to see if his problem is there.

Good idea!

**MoonRise** · Nov 01, 2009, 06:19 PM

Re: A Collection of Karmic Tips and Tricks

Quite a bit of work went into this. Thanks! I know that there will be a lot of reads for this thread.

**IgnorantGuru** · Nov 02, 2009, 12:06 PM

Re: A Collection of Karmic Tips and Tricks

I said above that KDE finally added a way to email a pic from the file manager,
but apparently they haven't (not in Dolphin at least). I was looking at
Krusader's menu, which is the file manager I use.

So here are more detailed instructions for how to set that up. Basically this
will allow you to right-click on a pic or group of pics and resize or email them
with one click. Very easy setup.

First, save the "repic" script above, let's say to /myscripts/repic. Then go
into the Menu Editor and create a new item. Call it "Resize to 800x600". In
the command box for the item, enter:

Code:

/myscripts/repic --size 800x600 %U

Save the menu and close the Menu Editor.

Next step is to associate the program "Resize to 800x600", which you just added,
with JPG files. If using KDE, go into your file manager, right-click on a JPG
file, and select Properties. Click the little wrench icon (Edit File Type).
Under Application Preference Order, click Add... Find the "Resize to 800x600"
in the menu that pops up, and click OK. Then just make sure "Resize to 800x600"
isn't listed first in Application Preference Order (you don't want that to be
the default way to open JPGs). Click OK, and OK again.

Now you can right-click on the JPG and select Open with... "Resize to 800x600".
The pic will be resized to a new file in the same folder (the original will
remain). You can do the same with a batch of pics at once.

Gnome is similar I'm sure. You can also use the file associations in KDE's
System Settings|Advanced|File Associations to set them up if you don't want to
do it in the file manager.

You can add other menu entries for other sizes the same way. Note that
"800x600" refers to the maximum horizontal and vertical dimensions
(aspect ratio is preserved). (If a pic is too small, it won't be resized.)

You can also add an entry called "Email Pic", with the command being:

Code:

/myscripts/repic --email %U

or

Code:

/myscripts/repic --tmp --email %U

The selected pics will be resized and put into an email. Note that this
requires KDE's kmail, but if your email client accepts emails with attachments
on the command line, you can adjust the script to use your client.

Also, if you want to resize a whole folder of pics, you can use a command like:

Code:

repic *.jpg *.JPG

For additional options:

Code:

repic --help

**IgnorantGuru** · Nov 03, 2009, 10:20 AM

Re: A Collection of Karmic Tips and Tricks

As I suspected, in the SSD CHANGES section, the mount /var/log is not having the
desired effect of protecting the SSD. The system starts log files before
rc.local is run. When tmpfs is mounted to /var/log, the system log files become
invisible, but they are still updated (every few seconds). So there is really
little gained mounting them in rc.local. Until the bug in mountall is fixed, I
don't know a way to prevent all these writes to /var. The SSD is still somewhat
protected if you added the commit= line in fstab. That way even though /var/log
changes every few seconds, the changes are only written to disk every few
minutes, which makes a big different over time. So you should definitely add
the commit=. Also note that you CAN still mount /tmp as tmpfs - the bug does
not stop that.

Here are modified versions of the SSDCHANGES scripts above which doesn't bother
mounting /var/log in rc.local. It still mounts /var/tmp, since that happens
before KDE starts and is thus useful. If you already ran the scripts above, you
can run these scripts and it will undo those changes, while keeping the changes
you still want.

The ssdchanges script - run with sudo.

Code:

#!/bin/bash
# must be run with sudo
# setup changes for SSD

# modify /etc/sysctl.conf to change kernel dirty page writeback time
test=`grep '\# I added to reduce disk activity' /etc/sysctl.conf`
if [ "$test" = "" ]; then
	if [ ! -e /etc/sysctl.conf-orig ]; then
		cp -a /etc/sysctl.conf sysctl.conf-orig
	fi
	echo >> /etc/sysctl.conf
	echo '# I added to reduce disk activity to 240 seconds' >> /etc/sysctl.conf
	echo 'vm.dirty_ratio = 40' >> /etc/sysctl.conf
	echo 'vm.dirty_background_ratio = 1' >> /etc/sysctl.conf
	echo 'vm.dirty_writeback_centisecs = 24000' >> /etc/sysctl.conf
fi

# Note: if you DON'T have a laptop, uncomment the line below
# to prevent changes possibly being undone
#chmod -x /usr/lib/pm-utils/power.d/laptop-mode

# edit fstab to mount ramdrive to /tmp
test=`grep '^tmpfs.*\/tmp.*tmpfs' /etc/fstab`
if [ "$test" = "" ]; then
	if [ ! -e /etc/fstab-orig ]; then
		cp -a /etc/fstab /etc/fstab-orig
	fi
	echo >> /etc/fstab
	echo '# I added to reduce disk activity' >> /etc/fstab
	echo 'tmpfs /tmp tmpfs defaults,noatime,size=1000M,mode=1777 0 0' >> /etc/fstab
	echo '# The following lines are disabled because of the bug in mountall' >> /etc/fstab
	echo '# These may be mounted in /etc/rc.local instead' >> /etc/fstab
	echo '# See [url]https://bugs.launchpad.net/ubuntu/+source/mountall/+bug/431040'[/url] >> /etc/fstab
	echo '#tmpfs /var/log tmpfs defaults,noatime,size=200M,mode=0755 0 0' >> /etc/fstab
	echo '#tmpfs /var/tmp tmpfs defaults,noatime,size=500M,mode=1777 0 0' >> /etc/fstab
	echo '#tmpfs /var/spool/postfix/public tmpfs defaults,noatime,size=50K,mode=1777 0 0' >> /etc/fstab
fi

# Replace rc.local for SSD changes
if [ ! -e /etc/rc.local-orig ]; then
	cp -a /etc/rc.local /etc/rc.local-orig
fi
cat << EOF > /etc/rc.local
#!/bin/bash
# above must be #!/bin/bash not default /bin/sh -e
#
# rc.local
#
# This script is executed at the end of each multiuser runlevel.
# Make sure that the script will "exit 0" on success or any other
# value on error.
#
# In order to enable or disable this script just change the execution
# bits.
#
# By default this script does nothing.

# mount ramdrives to /var/tmp and /var/spool/postfix/public
for dir in "/var/tmp" "/var/spool/postfix/public" ; do
	test=`mount | grep " on $dir "`
	if [ "$test" = "" ]; then
		sz="50K"
		md="1777"
		case "$dir" in
			/var/tmp )
				sz="500M"
				md="1777"
				;;
			/var/spool/postfix/public )
				sz="50K"
				md="1777"
				;;
		esac
		mount -t tmpfs -o size=$sz,noatime,mode=$md tmpfs $dir
	fi
done

# Set sda to use deadline scheduler
# Note: if these changes don't seem to take, try pasting them into a root console
#    (or with sudo) manually once then reboot
echo deadline > /sys/block/sda/queue/scheduler
echo 1 > /sys/block/sda/queue/iosched/fifo_batch

exit 0

EOF

chmod u+x /etc/rc.local

# If you run postfix, change postfix startup script so that rc.local runs first
# Note: This may need to be repeated if postfix is upgraded
test=`grep 'bash /etc/rc.local' /etc/init.d/postfix`
if [ "$test" = "" ]; then
	sed -i -n '
	1h
	1!H
	$ {
		g
		s/case "$1" in\x0A  start)\x0A/case "$1" in\x0A  start)\x0Abash \/etc\/rc.local\x0A/
		p
	}
	' /etc/init.d/postfix;
fi

exit

And the ssdchangestest script - run with sudo:

Code:

#!/bin/bash
# Test SSD settings

echo '###########################################################################'
test=`cat /proc/mounts | grep "^/ .*commit="`
if [ "$test" = "" ]; then
	echo 'BAD: cat /proc/mounts | grep "^/ .*commit="'
fi
test=`cat /proc/sys/vm/dirty_ratio`
if [ "$test" != "40" ]; then
	echo 'BAD: cat /proc/sys/vm/dirty_ratio'
fi
test=`cat /proc/sys/vm/dirty_background_ratio`
if [ "$test" != "1" ]; then
	echo 'BAD: cat /proc/sys/vm/dirty_background_ratio'
fi
test=`cat /proc/sys/vm/dirty_writeback_centisecs`
if [ "$test" != "24000" ]; then
	echo 'BAD: cat /proc/sys/vm/dirty_writeback_centisecs'
fi
test=`cat /sys/block/sda/queue/scheduler | grep "[deadline]"`
if [ "$test" = "" ]; then
	echo 'BAD: cat /sys/block/sda/queue/scheduler'
fi
test=`cat /sys/block/sda/queue/iosched/fifo_batch`
if [ "$test" != "1" ]; then
	echo 'BAD: cat /sys/block/sda/queue/iosched/fifo_batch'
fi
test=`mount | grep "tmpfs on /var/tmp "`
if [ "$test" = "" ]; then
	echo 'BAD: mount | grep "tmpfs on /var/tmp "'
fi
test=`mount | grep "tmpfs on /tmp "`
if [ "$test" = "" ]; then
	echo 'BAD: mount | grep "tmpfs on /tmp "'
fi
test=`mount | grep "tmpfs on /var/spool/postfix/public "`
if [ "$test" = "" ]; then
	echo 'BAD: mount | grep "tmpfs on /var/spool/postfix/public "'
fi
exit

**IgnorantGuru** · Nov 08, 2009, 03:22 PM

Re: A Collection of Karmic Tips and Tricks

I've set up a blog and download site where I can share some of these scripts.
It's kind of cumbersome to update and maintain them on the forum so I thought
this might work well. I am gradually polishing some of the above scripts and
others I have, and adding them to the blog site.
http://igurublog.wordpress.com/

Comments are welcome, both on the presentation and on the scripts and howtos.
It helps me to know what kinds of scripts people find useful - sometimes I don't
have a clue so it's hard to decide which ones to spend more time on. So if you
find something of use to you, please leave a comment (on the blog or here) and
let me know - thanks.

I just added an updated version of the scanpic script from the post above. This
one tries to detect your scanner's device name, and also lets you specify a
device on the command line. And there are a few other scripts up there as well.

Check the blog in the coming weeks for updates. I will be traveling later this
month but after that I should have time to add some more.