Back in 1986, when I first started with IBM, my first job was working on a software product called Data Facility Hierarchical Storage Manager (DFHSM). This did "Information Lifecycle Management" (ILM) by moving data sets from one storage tier to another. (The phrase "Information Lifecycle Management" was coined by StorageTek in 1991, and later resurrected by EMC a few years ago. As is often typical, things that appear new to the distributed systems crowd, are often well-established concepts in the mainframe arena).
To help explain DFHSM and its sister product Data Facility Data Set Services (DFDSS), an enterprising sales rep in Los Angeles named C.D. Larsen made a video called "Re-arranging the sock drawer". He explained that sometimes you want the socks you wear the most on the top drawer, and socks that you only wear now and again in lower drawers. DFHSM can re-arrange your sock drawer based on policy-based automation, determining which ones you wear most often, and moving the others down the "hierarchy" accordingly.
To explain DFDSS, he pulled out an entire drawer of socks, and move it to another level. DFDSS was able to do volume-level backups and dumps to tape very quickly, since it did not process individual data sets, but rather the entire volume image as a whole. These two products are now DFSMShsm and DFSMSdss components of the DFSMS element of the z/OS operating system.
Mainframes use an interesting naming convention for its data sets. 44 characters, divided up into qualifiers that are 1-8 characters long, separated by periods. For example:
The first qualifier indicated it belonged to me, that it was for my Project A, that it was a testcase, and specifically TEST1 job control language. Arranging them in this order meant that I could easily find all the data needed for project A, but if I wanted to keep all the testcase data together, I might have put that as the second qualifer instead.
On Linux, UNIX and Windows, most people are more familiar with hierarchical file systems, so the same file might be stored as:
Same concept. You set up a taxonomy of they way you want to organize your data, so that related data can be grouped together and easier to manage. Whereas we used to tell customers that "Qualifiers are your friend", we now tell people "sub-directories are your friend". This is true when organizing the files on your laptop, in your Lotus Notes, and in Second Life.
Since starting Second Life last November, I have picked up all kinds of free things along the way, and now have thousands of objects in my "inventory". Basically, its like keeping things in your pocket, when you want it, you just take it out of your pocket, and *poof* it appears magically on the ground. I was having a hard time finding things in my inventory, so I decided to re-arrange with sub-folders. This is done in-world, and I found it best to do this away from other avatars asking "what are you doing?" which can get quite annoying. Find a remote island or the rooftop of some building when doing "house cleaning".
I've arranged my main folders as follows. These all appear on a single screen, and makes it easy to find exactly what I am looking for.
- Body Parts
- Calling Cards
- Lost and Found
- Photo Album
In Second Life, you can make complete "outfits" which include your body shape, skin, eyes, hair, and clothes. However, saving away many outfits means duplicating a lot of items. Therefore, I separated them out. I keep body shape, skin, eyes and hair in the folder "Body Parts" and all of the clothing items under "Clothing". Under clothing, I separated everything out into the major categories:
I could have a separate folder for "socks", but I keep those in the "shoes" folder.
technorati tags: IBM, DFHSM, DFDSS, DFSMS, z/OS, qualifiers, taxonomy, Second Life, inventory