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After trying out ZFS on a handful of fitful USB keys I pulled out the AMS Venus T5 a 5 drive SATA RAID enclosure with an eSATA port for plugging into the computer. The Venus T5 was outfitted with 5 x 7200RPM 1TB Seagate Drives for the test. I was curious as to what the difference would be

RAID 0 setting has them all striped together. The Single Drive results are an average from all 5 drives. To keep in with the previous post I still used date +%s for the timings instead of using the more accurate time command.

Standard Test (5 cycles):

Extended Test (5 cycles):

As seen in the ZFS test on the USB keys it’s quite obvious that QuickBench 4.0 is useless in benchmarking a ZFS formatted drive in comparison to other formatted drives. ZFS isn’t supported so it isn’t surprising.

As a continuation of a more consistent test we then copied a 903MB file (Xcode 2.5) and a folder of of 1500 0 byte files numerically named.

date +%s; cp ~/Desktop/SpeedTest/xcode.dmg DESTINATION; date +%s;
cp ~/Desktop/SpeedTest/*.txt DESTINATION; date +%s

With much better hardware the actual throughput information is a lot more interesting.

In the quest to sate my curiosity of the viability of ZFS for replacing hardware RAIDs I gathered a few extra USB keys that were lying around my office in hopes to see just how much of a difference in terms of numbers one can find between a single USB key, a software RAIDed set and the new Zettabyte file system (ZFS) that will be more predominantly shown in Snow Leopard.

I used two identical Kingston DataTraveler 2.0 Media DTI/1GB keys. Key 1 reports 980MB, whereas Key 2 reports 984MB. I had originally 4 keys lined up to use, but the two other keys I had would not format. I am unsure why there is such a difference in reported size, and the two keys that wouldn’t format would both report 970MB.

Because ZFS is a software RAID I was comparing it to the software RAIDs created by Apple’s Disk Utility (Version 11.1 in Mac OS X Leopard 10.5.5). The ZFS installation was the 119 release that was put on MacOSForge on July 23rd, 2008 and is still very much under development as the Mac OS X port isn’t even complete yet.

All test performed using QuickBench’s Standard Test, which is a test that transfers several small files ranging from 4KB to 1MB:

Given the insane speed increase seen by ZFS (which I assume is greatly improved by it’s ability to use compression reducing the amount of I/O work) which makes the test sound horribly flawed I redid the test using the Extended Test in QuickBench 4.0.

Extended Test (20-100MB)

In this second test we were again getting wildly fast results that didn’t fit with reality - the files divisible by 30 were wildly faster than any other result.

Lastly a very simple copy using the command line copy:

date +%s; cp ~/Desktop/Reverie_Final_Cut2_midres.m4v DESTINATION; date +%s

As a baseline a simply copy on my 5400RPM drive in the MacBook Pro this was done on takes 11 seconds.

Caveats: The RAID 1 copy trials ranged from 13 seconds (subsequent trials) to as much as 39 seconds (the first copy). While ZFS was 11 seconds each and every time. Also the commands used are going to be imprecise - if I wanted it to be more accurate instead of easily out by as much as 1 second I would have used the time command.

As a continuation of a more consistent test we then copied a 903MB file (Xcode 2.5) and a folder of of 1500 0 byte files numerically named.

date +%s; cp ~/Desktop/SpeedTest/xcode.dmg DESTINATION; date +%s;
cp ~/Desktop/SpeedTest/*.txt DESTINATION; date +%s

So what does this all mean? From the first two tests we can see that ZFS does improve throughput but our standard QuickBench tests aren’t any help of determining how much because of ZFS’ difference in dealing with files giving us consistent odd results. The more practical test of copying an H.264 file and the large file with many small files gave us inconsistent results. There isn’t anything concrete in my non-scientific results but I’m looking forward to Snow Leopard being released and ZFS becoming a full fledged filesystem citizen in the Mac OS - if only because with maturity ZFS might be a faster option for a RAID system.

Tomorrow the same file copying tests will be performed on a 5TB RAID connected to the computer via eSATA for kicks.

One of the very first programs I install on any machine I will be spending a good deal of time on is LaunchBar. I am a self confessed LaunchBar whore because of the amount of time it saves me from going down to the Dock or having to find the Applications folder to launch Applications on top of being able to calculate, do web searches and manipulate files just from a few keystrokes.

Here are three snippets I’ve added to my LaunchBar configuration that make my life a bit easier:

Add /Library/CoreServices as a folder to search - it means you can access applications like Screen Sharing and a few other lesser known applications without digging.

Searching Apple Mailing Lists: http://search.lists.apple.com/?q=*&cmd=Search%21&form=extended&m=all&ps=50&fmt=long&wm=wrd&wf=2221&sp=1&ul=

LargeText: x-launchbar:large-type?string=*

Lastly a couple other tips that I keep running up against:

1. ** allows you to do powers of in the calculator. Not ^.

2. If you consistently misspell something (eg. LIHGR instead of LIGHR for Lightroom) you can set the abbreviation by typing in something that does bring up the file or application and then press Command-Option-A (Select->Assign Abbreviation with the mouse) and then type in the misspell that you keep typing.

I came across a process running on my iMac at home tonight that was consuming a fair chunk of RAM, and a consistent 40-50% of my CPU while accessing each and every hard drive I have hooked up. The process in question is called build_hd_index and is part of Apple’s built in Remote Management software in OS X.

The specific file can be found in /System/Library/CoreServices/RemoteManagement/ as part of ARDAgent.app (ARDAgent.app/ Contents/Support/build_hd_index) and is used by the program (Apple Remote Desktop Agent) to build user and applications reports to be sent back to Remote Desktop Admin (an Apple program for managing multiple computers that is awesome). The reason this was even turned on was that as part of an attempt to get a VPN server working I added my home computer to Remote Desktop Admin on my work computer. By default (as it’s set in my preferences and I believe always default) it will gather reports on certain data which run at midnight in order to cache the data on the computer running Remote Desktop Admin so you don’t have to requery such information every time you wish to look at it.

A quick Google search on build_hd_index showed several other people having issues with it suggesting ways to neuter the process (which would break System updates) or other attempts to disable it.

To turn it off, on every computer running Remote Desktop Admin you need to tell it to stop collecting data (Get Info on the computer) or you can force this by removing the plist file in charge of ARDAgent at /Library/Preferences/com.apple.ARDAgent.plist . More of this is covered in detail in Apple’s KBase article.

So as of a result, since my work computer is a laptop and is not on, let alone at work at midnight I’ve turned off uploading information at scheduled intervals - however I still want my work computers to cache the data as the information is useful to debugging why something may be happening.

This is a repost of a much older post that was lost when I transitioned from Moveable Type 3 to 4.

I personally like using WebKit nightlies as my main browser as it’s more or less Safari with a better, faster, and much more current rendering engine underneath it. That and the gold logo looks much better than the silver. It does have bugs occasionally (for example I was unable to post comments to Flickr with WebKit nightlies for a couple weeks) but all in all the experience is very positive. This is the script I use to keep WebKit updated whenever it bugs me for an update. I use an alias in my .bashrc file so I can just type ‘wkupdate’ to run the shell script. The best part is that if I copy it and I’m still using the program the changes won’t take effect until I restart but it allows me to copy it still. (Not advisable however)

EDIT: Updated 12/30/08 - Fixed URL check. Realistically you should be looking for the latest source at the link below:

As always this script can be found in my git repository on GitHub.

At work we sometimes receive DVDs that we need footage off of that are locked. They will play back fine in DVD Player but we don’t want it for playback. The resulting DVD images are always titled SONATA_VOLUME and are created by a stand alone Sony DVD Recorder.

In order to copy the VIDEO_TS file off of the DVD you require sudo access but given that sudo access is limited to administrators (and not the editors) - this gets to be a bit of hassle because I have to be called to copy the DVD which adds unnecessary overhead to just get some footage off a simple DVD.

The solution? Create a droplet application (in this case AppleScript with shell scripts) so the editors don’t have to disrupt their workflow to get me to unlock the footage they need.

The source follows:

After much (okay very little) persuasion from Matt and coincidentally a well written breakdown on how he has set up his WordPress installation I’ve pulled the trigger and installed WordPress. The installation replaces my MT4.1 installation that languished under the wait for me to find some time to design the new blog and accompanying photo blog on mcjones.ca. I had even got so far I had it written it out and sketched in a notebook. Finding the time to sit down and actually code it however never came to pass as when I did make time it was the last thing I felt like doing.

So please bear with some minor growing pains as I decide and modify a theme for WordPress - I’d still love to go with the design I made but since that is never going to come to fruition I should move and start creating articles that interest me.

After seeing this error popping up a lot while having issues with my internet connection dropping packets left and right I searched CFNetworkErrors.h for what the error code meant (since Google didn’t say much other than it appeared in 10.5.3). The line in question is: kCFErrorHTTPConnectionLost = 302,

So if you get kCFErrorDomainCFNetwork: 302 errors, it’s because the HTTP connection was lost somewhere along the way. As to what causes it can really definitely seem like voodoo.

The following AppleScript snippet figures out how many tabs are open in the frontmost window and spits it out to Growl. Helps when I don’t feel like counting how many tabs I’ve opened in WebKit/Safari. Note: To get this to work with Safari change WebKit to Safari.

Note: This was fixed in Leopard. Unsure if it was fixed in 10.4.11 as I don’t use Tiger anymore.