Hard Disk speed comparison

These are five hard disks that I have in three machines that I frequently access.

Machine	Drive	MB/s	Model	Description
Pavilion	C	35/35	ST3250823AS	Seagate Barracuda 7200.8 ST3250823AS 250GB 7200 RPM 8MB Cache SATA 1.5Gb/s 3.5" Hard Drive -Bare Drive
Pluto	C	225/225	PFZ128GS25SSDR	Patriot Torqx PFZ128GS25SSDR 2.5" Internal Solid state disk (SSD)
Pluto	E	60/120	ST32000542AS	Seagate Barracuda LP 2TB 3.5" SATA 3.0Gb/s Hard Drive -Bare Drive
Monster	C	150/200	WD3000GLFS-01F8U0	Western Digital VelociRaptor 300GB 3.5" SATA 3.0Gb/s Internal Hard Drive -Bare Drive
Monster	D	90/110	ST31500341AS	Seagate Barracuda LP 1.5TB 3.5" SATA 3.0Gb/s Hard Drive -Bare Drive

I was thinking of replacing the 250GB Seagate in the Pavilion to improve performance on that machine but wanted to get an idea of what sort of performance boost I thought I might be able to get so I copied some hard disk benchmarking software (ATTO) onto each of the machines and ran it.

The MB/s column shows the write/read speeds measured for each disk. This is a rough average for each disk.

My surprises were as follows:

• The solid state drive (SSD) was not much faster than the velociraptor.
• The seagate 1.5TB had a faster write time than the 2TB. (It doesn't feel faster, it feels slower.)
• The 2TB driver is less that twice as fast as the old 250GB Seagate. (Again, the 2TB drive feels much faster.)

I've decided to replace the Pavilion's 250GB Seagate with a 2TB Seagate. The bottleneck with that machine at the moment is the hard disk and I'm confident that I'm going to get at least a triple speed improvement even though the numbers don't give that.

Since I installed my Windows Home Server nothing has crashed on my network so I have been unable to try out recovering a hard disk from its backup. I plan on using this new disk as an opportunity to try this with the Pavilion machine. I will add the new hard disk and then set the bios to treat this disk as the boot drive. I think that I then have to generate a recovery CD from which this machine will boot and restore the OS etc. to the new disk.

I'll post a link to my results here when done.

Destroying a Hard Disk

A number of years ago I got myself a Maxtor 250GB external hard disk which at the time I used for all my backups. It cost me a fair penny then (2003) and I can now in 2009 buy 4TB of space for the same amount. Don't think that I'm complaining though, I think that's great progress.

Like all good hard drives it eventually died but it died a slow bit by bit corrupting death. It started to become inconsistent (that's when I should have taken an image of it) and then just started to corrupt and not be able to read data. Luckily I manage to recover all my important data and just lost a few albums of songs and movies that I could easily buy again.
The drive had only lasted about 2 years and Maxtor refused to entertain the idea of replacing and knowing how much I'd spent on it I didn't want to through it away it so it went into the box of computer parts that every geek has.
Years passed and during a cleanup I agree with myself that it had to go. I really couldn't remember what else was on it but I was pretty sure that a good hardware recovery technician could get data off it so I wanted to destroy it before disposing of it.
To this end I pulled out a drill and started drilling holes in it. The white box around the photo below shows a broken drill bit and the other end of the bit is lying on top of the circuit board.

With a larger and stronger drill bit I was able to get some deeper and more crippling holes into the disk before I decided that I had limited data recover-ability from it.

When you read the instructions on how to handle these devices they always tell you to discharge any static before handling and work in a static free environment etc. I ignore all of that when I was doing this.

Age Analyzer

As part of the text classification work that I do I follow the uClassify blog who have just release a new web site called Age Analyzer. which guesses the age of the author of a blog. I plugged in the URL of this site and it guessed me in the 26-35 bracket. This would be flattering if you were to look at me but I find it insulting that my writing is considered this immature. It should have put me in the 36-50 bracket.

My friend Rob Manderson's eloquent prose has aged his Ultramaroon Rises Again blog in the 65-100 range (I'm sure you're not that old Rob). Dan Esparza's Esta Nublado puts him at a very young 18-25, and Bill Brown's New Clarion puts him in the 65-100 bracket while his bblog looks a little more accurate at 26-35.

The Evil Solution User Option SUO file

I have a Visual Studio solution that's started taking longer and longer to load. In fact it was taking up to 5 minutes to load this solution which meant that I'd leave the solution open for days just so that I didn't have to reload it. Another symptomatic clue that all was not well in Denmark was that it was taking several minutes for the IDE to be usable after I stopped a debug session with Shift+F5.

My first stab at a solution was to create a new one in a different directory and add all my projects to it. Worked like a charm and the new solution loaded lightening faster (couple of seconds) and I could exit the debug session in about 3 seconds.

Although happy that I'd solved the problem I was then lucky enough to notice that in the original folder next to the solution's .sln file there was a Solution User Option .suo file which was a whopping 11Mb in size. I deleted this file and opened the original solution and discovered that my solution is now loading and exiting debug lickety-split again.

It might be my unorthodox way of exiting debug sessions with Shift+F5 that's causing this file to grow in size. I'll keep an eye on it's future growth and report back here if I learn anything new.

Even Faster Web Sites

Just been reading Even Faster Web Sites. I had never heard of comet before I read this but it makes sense and I'm looking forward to trying it.

Comet is a long-held HTTP request allows a web server to push data to a browser, without the browser explicitly requesting it.

I was a little bit surprised that the book only gave two pages to CSS Sprites. My testing shows that sprites can significantly improve web site load times if the site has multiple small images coming from the server.

Web app efficiently is going to start playing a more and more significant role as we return to the mainframe model with cloud computing. Many of the cloud computing providers are charging by processor cycles so the fewer of these your app uses the less expensive it is to run in the cloud. On top of that because you are processing your requests faster your site will be more competitive.

SQL Injection Attack part 2

Since I last wrote about a SQL Injection Attach that one of my sites received I took measures to prevent it and now reject a URL with @(cast in it immediately and don't process it any further. This has worked well over the last year and a half and no further attacks of that type have made it into the logs.

I have now started to see URL requests with the following pattern:

...&whichpage=3%20and%20char(124)%2Buser%2Bchar(124)=0

The significant part comes after the =3:

 and |+user+|=0

No idea what they're trying to achieve with this...

Rotate or flip image through Y-axis

I've been trying to work out how to rotate an image through the Y-axis and display its mirror image on a web page. One of the problems that I faced was trying to find the right word(s) to search on as rotate (so I discovered) is used to refer to rotation through the Z-axis most of the time.
I finally found a solution in Silverlight 3. Here's the code...
<Image Source="Jellyfish.jpg">
    <Image.Projection>
        <PlaneProjection RotationY="180" />
    </Image.Projection>
</Image>
...which does exactly what I'm looking for.
My favorite image editing program (Paint.Net) refers to this as Flip Horizontal which I think is completely misnamed.

<PlaneProjection RotationY="0" />

  <PlaneProjection RotationY="180" />