Documenting Problems That Were Difficult To Find The Answer To

Monthly Archives: August 2016

Installing OpenRA on Xubuntu 14.04

I had to run the following command after downloading the OpenRA deb file:

sudo apt-get install libsdl2-2.0-0 mono-runtime mono-runtime-sgen liblua5.1-0 mono-runtime-common mono-gac mono-4.0-gac libmono-corlib4.5-cil libmono-security4.0-cil cli-common libmono-system4.0-cil libmono-system-core4.0-cil libmono-system-drawing4.0-cil libmono-system-data4.0-cil libmono-system-numerics4.0-cil libmono-system-runtime-serialization4.0-cil libmono-system-xml-linq4.0-cil libmono-posix4.0-cil libmono-data-tds4.0-cil libmono-system-configuration4.0-cil libmono-system-enterpriseservices4.0-cil libmono-system-transactions4.0-cil libmono-system-xml4.0-cil libgdiplus libmono-system-security4.0-cil libmono-i18n4.0-all

Want to Slow Linux ZFS Flushing/Syncing to Disk Every 5 Seconds?

So you’ve got ZFS on Linux and you notice your hard drive LED light up every 5 seconds. How can you slow that down?

The zfs_txg_timeout parameter is described as:

~# modinfo zfs |grep zfs_txg_timeout
parm:           zfs_txg_timeout:Max seconds worth of delta per txg (int)

You can check the current value of this parameter:

~# cat /sys/module/zfs/parameters/zfs_txg_timeout

To verify this is the parameter you want to change, set this to 10 and count the number of seconds between the hard drive light coming on:

~# echo 10 >/sys/module/zfs/parameters/zfs_txg_timeout

Once you know this is the parameter causing the hard drive activity you can tell the ZFS module the default you want it to start with on next boot by editing /etc/modprobe.d/zfs.conf and adding a line similar to the following:

options zfs zfs_txg_timeout=30

Take care when changing this number as it may result in a higher probability of lost data in the event of a power outage.

Thunar and Ristretto on Xubuntu 14.04 Do Not Render Thumbnails

I was puzzled and searching all over the Internet for an explanation why the file explorer (Thunar) and the image viewer (Ristretto) were not displaying thumbnails for JPEG files. I know they had rendered them before. I tried all sorts of things, deleting local cache (~/.thumbnails/* and ~/.cache/thumbnails/*), ensuring various packages had been installed.

Finally I stumbled across this forum post which gave the necessary clue:

A package called tumbler is needed for thunar to automatically generate thumbnails.

I checked to see that I had tumbler:

~$ dpkg -l |grep tumbler
ii  libtumbler-1-0  0.1.30-1ubuntu1  amd64  library for tumbler, a D-Bus thumbnailing service
ii  tumbler         0.1.30-1ubuntu1  amd64  D-Bus thumbnailing service
ii  tumbler-common  0.1.30-1ubuntu1  all    D-Bus thumbnailing service (common files)

Then I checked to see if a tumbler process was running, and proceeded to kill it:

~$ ps fax |grep tumbler
21322 ?        SNl    0:01          \_ /usr/lib/x86_64-linux-gnu/tumbler-1/tumblerd
~$ kill 21322
~$ ps fax |grep tumbler


~$ killall tumblerd

Now when I opened a thunar file explorer the thumbnails were being rendered, and also rendered in ristretto, too.