Polyglotism

Lately, I've been educating myself on the topic of what is commonly called NoSQL, and this nice presentation by Martin Fowler made me think about stuff I've already written about earlier. The same thing can also be found on a talk on data storage technologies employed in Craigslist.



The key phrase was polyglot persistence (@~51 mins in the video). Not that I wouldn't probably have heard it already earlier, but now the ultimate meaning finally dawned on me. It means, that to build a system - one that is highly performant, at least - you probably need to be able to take advantage of the different DBMSs that are around. The same way that multi-lingual developers push the idea that you need to use the language that is right for the job. So the diagram Fowler gave on polyglot persistence could be extended with programming languages with which the different parts of the system have been built with, and probably also with OSs the parts run on, and so on. There is a reason for dozens of DB brands and programming languages and whatnot existing, and it is the attempt to produce proper tools for specific problems. I can see this could also lead to a sprawl of diversifying computational environments, but I guess the constant popularity contest that goes on between products makes either the products converge or the niche options quietly fade away with the more popular ones gaining market share.

All this polyglotism further widens the options for a fresh wannabe ICT specialist. There certainly is a need for narrow deep expertise (to be able to know something like the Spring framework from top to bottom one really needs to spend considerable time with that alone), but I do not see that it would become very common for companies that are not actually huge in size and less than 100% technology oriented to hire bunch of specialists of different areas. Or they could, but then again they could hire them just as well as consultants since they are not likely to need each one of them equal amount of time constantly, and if the team members do not know much about each others areas of expertise they really can't be assigned to work on the same task together. My experience from the service sector is that there is a huge need for a team of people small enough that it can constantly be kept busy with the ongoing tasks and that you can throw at any kind of a problem and they can handle that based on their collective wide experience.

What I am after here is that even though I've been mostly using Oracle (from version 8 onward, I think) as the data back-end in my professional life,  the potential of interesting non-RDBMS encounters is highly rising. All along the road I've been running into cases where it is not feasible to stick to the good ol' 3NF of data and instead denormalising to get performance - something that the NoSQL folks are very fond of. This far it has been a convention that if an application needs a DB (bigger than can be reasonably embedded within the product on the same server), it supports one or more of the big traditional RDBMSs. Now I already see RHQ including Apache Cassandra in the package, and even though Cassandra comes bundled with the product, one basically needs to install it on a server of its own for practical use - so basically it can be said RHQ requires Cassandra in addition to one of the supported RDBMSs. Personally, this made me think of how I can sell the idea of requiring another server for application server monitoring to my superiors...

Your old sins will come to pay you a visit once more

Some time ago, I had to shut down both of my Linux boxes at home since I needed to cut off electricity from some rooms while installing a ceiling fan (remember working safety!). All was well with the fan after switching electricity back on but then I tried getting the older server box up. It said it didn't have any disks. Well, that is a sure way to pump up stress hormone levels, and it did work on me again. The first suspicion was that since the hardware is rather old and had not been off for a looong time maybe some electronics just had died. But no, it didn't see either of the attached disks. Since that box was serving also as DHCP, DNS and gateway for LAN, and it was getting late in the evening, I just hacked the needed services up on the desktop box which luckily had pretty much the same firewall config already. DHCP didn't still work, though, and since we were about to leave on a holiday trip I just left it that way (later on I discovered there was just a stupid mistake in the config but that's the way it always goes, right?). Professionally it felt bad to leave my lady's web site offline, but she didn't seem to mind the long SLA.

After returning from the trip I took another try on trying to get the issues sorted out. Trying out a live cd proved that the hardware was alive and well. I had already been suspecting something about udev earlier based on some googling and found some info on kernel options CONFIG_SYSVS_DEPRECATED and CONFIG_SYSVS_DEPRECATED_V2. Disabled those, recompiled the kernel and behold, all was well again! I have absolutely no recollection why those were enabled (probably for supporting some older utilities), they had been that way for years already. Seems like Debian had evolved their udev implementation so that it had become incompatible with those features somewhere after the last reboot (which on the server box was 1.5 years earlier as I found out from the uptime logger afterwards). Serves me right for keeping a feature that is clearly meant to be transitory enabled for so long...

Well, this week I noticed that I had no sound on the desktop. First I just thought it was due to Flash which was not working in Opera anyway, so I installed Gnash and its dependencies. Too bad there was still no sound. No sound from much anything, actually. I got a crash course on sorting out Pulseaudio issues, but the end result was that I only had a dummy sound device available and even though Alsa seemed to recognise the emu10k1 device, there was just no sound at all.
Then I got a flash of enlightnenment. Those damned kernel options... the kernels were identical excluding things related to differing HW on the boxes, so also the desktop had the same deprecated features enable. Needless to say, disabling them made sun shine on me again. They really do seem to mess up with udev in unpredictable ways.

Uh, I just need to start paying more attention on what these boxes have installed and configured and not let them deteriorate....

Hazards of sitting

Having been reading monthly occupational safety reports at work has increased my consciousness on safety related to work in general (very good for preventing some stupid home injuries) and electricity related risks (also very good thing to know if you are the kind of guy who doesn't fear to make some minor changes to home electricity, like installing a ceiling lamp that doesn't have the fancy and safe kind of a plug for connecting it). Other than that, I guess, for a guy who sits at the desk all day long the most likely accident at work is slipping on the office floor. And oh yes, I have once dropped a thick folder full of papers on my big toe, which resulted in a small bruise. Probably not reason enough to request for safety shoes with anti-slip soles and toe protection, though.

Those reports and subjective experience has also increased consciousness on the fact that long term sitting in front of a computer is a hazard to one's health. Not an acute one, though, and perhaps it is not that high profile on corporate health and safety agenda - except (hopefully) in software houses. Generally computer work is taken as such that it can be done in a condition where manual labour is not anymore possible (the most important muscle in a specialist is the brain, anyway). However, there is potential for many kinds of pain which might even be debilitating and thus affect productivity, so to me it looks a very real threat for working health.

I remember times when stiffness and tension caused by crouching over the keyboard was easily taken care of by some physical workout, stretching and a walk outdoors. By that time I didn't do yoga asanas, but I'm sure those would have worked, too.

I miss those times. Nowadays I'm happy if there is no notable tension and the stiffness is not painful. I've increased my awareness on the condition of my body as well as my posture, and I try to have short breaks during the day for doing some exercise and stretching at my desk. I do asana practice at least a couple of times a week, and have tried several kinds of treatments and therapies (different kinds of massage, acupuncture, reflexology...) and go to work by bike or foot. I ran into a good article on the subject and the theory given there on the reasons for the continued stiffness and discomfort seem very logical to me: the stiffness kind of works its way into the different tissues and thus in the end it's not just the muscles that behave badly.

So far I haven't used any occupational health care services since the situation is not outright bad, but I'm concerned of the directions of things for the sake of myself. I'm also pretty confident that the condition is indeed profession related (type of profession and condition do match).

The thing I'm happy about is that there is one common computer job related injury that I've managed to prevent so far - the carpal tunnel syndrome. I've been paying a lot of attention to hand ergonomy since pretty young which must have helped a lot. Maybe if I had been just as aware of the possible results of bad posture, too, things might be now different...

The reason I'm writing this is that during all these years I haven't met too many colleagues who would have indicated that they are really aware of these things. It's pretty common for office workers to go a gym regularly, and that is most likely a very good thing to do. Many might also have other hobbies that are good for the upper back area (I've heard that for example golf is great physical exercise in this sense). However, I fear that I'm not at all alone with this issue and it's worth the effort to bring up the subject.

Thanks for reading and now go do some stretching and make your body happy!