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Posted by ajt on Wed 3 Apr 2013 at 16:00
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Sometime this spring (when it arrives) I will buy a new desktop system. It will probably have two block devices: a traditional SATA large capacity hard drive and a much smaller and faster flash drive.

The theory says that cheap flash drives are much faster and will even probably outlive mechanical spinning disks. Flash systems do slowly go bad so use wear-levelling software in the controller to maximise life. The other problem with flash drives is that they are relatively small, so a larger drive either in the box or on the network is required given how much space life takes up...

I've no plan to join the two drives together with LVM, it seems pointless, instead they will be kept separate and one mounted onto the other. At the moment most of my systems use ext3 except one box which uses ext3 and XFS.

If I install a new box from the Wheezy ISO I'm guessing I'll get ext4 as default. I gather this is the logical upgrade from ext3 until something fancy is really ready and it is not an all singing-dancing next generation filesystem. Does anyone know how it compares with XFS on large disks or flash disks?

I'll probably use ext4 on the flash disk (root & boot file systems) and XFS on the spinning disk (/srv) as it's where I'll dump my media files which aren't small and XFS is supposed to be good for that, unless it's not worth the effort.


Posted by ajt on Wed 27 Mar 2013 at 18:56
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Someone asked me to test the speed of some Devolo 500AV ethernet over mains units I have as compared with some older 200AV units. In preparation I ran a simple test from my desktop box (that I plan to replace) to my server showed a throughput of about 333 MBit/s over a GigE switch. My younger laptop to the same server with a more modern (but still cheap) NIC gets 727 MBit/s to the same server over the same switch.

The desktop is using the common (at the time) Marvell Technology Group Ltd. 88E8001 Gigabit Ethernet Controller (rev 13) and the skge driver. ethtool reports all is well and that it's running at 1000 Mb/s as expected, but it clearly can't manage that on a simple iperf check.

Now I am planning on replacing the box anyway but just wondered if anyone knows and good tuning tips for Gig Ethernet?


Posted by ajt on Fri 22 Mar 2013 at 21:30
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It's a while since I bought my desktop PC. I tend to keep kit a lot longer than most of the people I know, indeed I still use kit that is older and slower than what some people throw away!

My desktop system is now getting too slow and full. I would never say I'm a good photographer but I do take pictures and the ancient 120 GB drive on my desktop system is full. I've got a lot of that backed up on my home server but even so the drive is just full. It also doesn't have enough memory or CPU grunt to edit a decent sized RAW image in GIMP. It's swapping far too much.

The best thing to do is buy a new box. I think that a 180 GB flash drive for root and a 2 TB hard disk for bulk storage should hold the OS and my pictures for a while. RAM is reasonably cheap so I'll probably go for 16 GiB off the stuff which should allow the system to breath more than it is with just 2 GiB that it has now. Not sure on the CPU, the quad-core AMDs are pretty cheap and come with a decent built in GPU but the twin-core Intels are faster if more expensive.


Posted by ajt on Wed 21 Nov 2012 at 22:10
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This week I got a pctv "nanoStick T2" USB DVB-T/T2 decoder for my PC. I plugged it into my ancient Debian desktop box running Wheezy and the kernel detected it at once. Kaffeine works out of the box, but VLC and SMPlayer both needed the dvb-apps package installing and a manual tune running to give them a channels file to work from.

We have direct line of sight to a major transmitter so even the little indoors aerial works quite well. I may still install a loft aerial to improve things mostly because the supplied aerial doesn't stick very well to wall paper - it wants a nice shiny surface like glass!


Posted by ajt on Sun 1 Jul 2012 at 14:29
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Last XMas I swapped my father's tiny Viglen AMD Geode based PC for a faster desktop system salvaged from the skip. That left me with a small Geode based system to play with. It's been sitting on a shelf between an external hard disk and a switch for quite a few months...

Today I thought I'd better boot it up and see what I can do with it. It was running Debian Lenny and KDE3, so it was due for an upgrade to Squeeze. Rather than let it try and force KDE4 onto it, I first removed most of KDE3 and a whole raft of GUI tools, I'll be using it as a server. After quite a few packages were removed I then did the dance and started to upgrade to Squeeze.

I have apt-cacher-ng running on my server, so the download wasn't too bad as lots of stuff for stable was already cached. At the moment it's doing the main upgrade dance as setting up the various packages it's installed. I will have to purge another batch of GUI stuff - I don't need GUI web browsers on a server.

I may even upgrade it again to Wheezy - it's looking pretty good - and as it's about to go into freeze it may be worth it now. It's only a toy server at the moment - so not important for anything yet. Once I've got wake-on-LAN working to my current main server, it may be time to swap them over so the big server can sleep most of the time.


Posted by ajt on Sat 28 Jan 2012 at 18:04

Last year I bought a Canon DSLR camera. As part of the deal, I agreed to use it and not let it gather dust in a corner. One of the things I've been doing is trying to take regular pictures and upload them to a daily photo blog.

For most of last year I was managing to load one or two pictures per week at best. Since Christmas I've been able to maintain a daily stream - while only a third are actually DSLR images - I think it has been useful forcing me to think creatively and my DSLR has been used more than it would have been otherwise.

If you take pictures and have them available digitally it's an interesting idea to have a photo blog. While it may seem a chore, it's not, like all things it does help to practice and you don't have to take a picture every day...

Here is my photo blog in case you are interested


Posted by ajt on Sat 28 Jan 2012 at 17:37
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Just when things are going well they start to not go well. Last weekend the power supply suddenly died in my seven year old desktop PC. Well actually at first I didn't know what had died but I borrowed a PSU from a friend and confirmed the rest of the PC was okay.

I've ordered a replacement model from a local supplier, and even though I plan to replace the PC within the next 2 years anyway I've bought a silent high efficiency model to see if they make a real difference to the noise the PC makes.

As things go it's not going to break the bank but I don't like it when things break.


Posted by ajt on Sat 19 Nov 2011 at 17:59
For a while I was running the ATI fglrx driver on my desktop box. It was almost unusable with KDE4 so I switched to Fluxbox, but even then it was painfully slow. Eventually I gave up with ATI and installed the open-source Radeon driver. After a purge of the ATI components and a reboot Fluxbox was much more responsive. In fact it is now sufficiently fast enough to run KDE4 properly.

It was faster running Squeeze but at the moment in Wheezy it is at least fast enough to use again.


Posted by ajt on Sun 14 Aug 2011 at 14:42
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I'm not happing much luck with my Wheezy desktop system at the moment. Ever since Sarge I've run Debian testing on my desktop with a constant upgrade. My home server and other family systems all run the current Debian stable. I know that testing isn't perfectly stable and things break - the point is the point of testing, to test things in case they break so that they are fixed when the next stable is created.

At the moment lots is broken and has been for more than just a few days. I submit bug reports but as is often the case I get no response or if I do they aren't helpful. I'm not complaining, I accept that testing isn't production quality and it does break from time to time but it seems more broken than usual at the moment.

AMD/ATI fglrx driver is unusable at the moment. X/KDE4 is horrendously slow to the point of being unusable as a desktop system. The open-source radeon driver is perfectly usable - though not as fast the closed-source fglrx is when it's working well.

Mid-week I installed Linux 3.0.0 as my kernel. Suffice to say it just panics when X starts or when KDE4 login is in process. Doesn't matter which graphics driver I use and the timing isn't consistent but if I don't boot into X, it's okay if it stays in text mode. If you manually start X after being on the console then it's okay too - but that's hardly a sensible way of doing things.

Google Chrome has been pretty dire of late, exceptionally slow on sites like twitter or Google's own Plus. Today (version 15.0.849.0-r96325) it just seg faults as soon as you try to start it. As a result I'm now running Iceweasel 5.0.1 which is actually a pretty good browser, the 3.x branch had got horribly slow in comparison to Chrome.

At least the jam making has been going well!


Posted by ajt on Tue 19 Jul 2011 at 12:23
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I followed the suggestions in this blog article Encrypted partitions with Ubuntu/Debian. In Wheezy, KDE4 finds the USB key prompts for the password, then shows you the unencrypted volume and you can mount/eject like any other USB key.

The problem is that this doesn't work in Squeeze. KDE4 prompts you for the password, and it creates the device-mapper entry, but it doesn't allow you to mount/eject the USB key from the GUI. While its a irritation, it's easy to manually mount/umount the drive from the command line, but it's a problem for desktop users.

I don't know enough about the innards of udev, udisks, D-Bus, HAL and KDE4 to know where to look for a fix. A quick hunt through the Debian bug reports suggest that this is a problem and it's not really a KDE4 problem as it also impacts GNOME users too - but so far no solution.