I booked a trip to an indoor ski centre, for my first ever snowboarding lesson. Seeing that I am an absolute beginner, and the snow centre has a main slope and a smaller slope, I assumed our lesson would be on the smaller slope, or certainly at the lower part of the main slope. How wrong I was. The lesson was up towards the higher part of the main slope. And we started by learning to control ourselves using the toe edge of the board. That meant we were facing up the slope with our backs to the way we were travelling!
Working on a system the other week, I decided to use only one of the two application servers, since they were identical machines with the same software loaded, and I only needed one machine for the test. I checked the settings, the test script I had written, the processor load and the network connection, but all to no avail - the test always failed. Over a week later, I tried the other machine and the test took just 2 seconds to run correctly. The machines might have been identical, but one of them had a hardware failure!
And I tell my students always to list their assumptions, and always check that the assumptions are valid. Now I have slipped up twice within the same week. One of the principles of the Baha'i Faith is "Independent investigation of the truth".
Saturday, 25 August 2007
Friday, 24 August 2007
Where are all the scientists?
As has become a habit over the last few years, the release of the GCSE results has been accompanied by comment in the media on the decreasing numbers of students taking mathematics or science.
Personally I am not surprised. What role models do our youngsters have? What is portrayed in the very media that bewail the lack of science students? It seems to me that the only role models portrayed are the sports personalities and the celebrities of the showbiz world. Whenever scientists appear, they are often portrayed as badly dressed, speaking words that most people do not understand and frequently lacking in social graces.
Also, perhaps, our concern for the safety of the pupils in schools has led to the curtailment of many experiments in classrooms. Science is now seen by many as 'boring' as much content is conveyed by watching videos. Gone are the times when pupils were let loose with geiger counters and radioactive materials (even though they were less active than the luminous paint used in the wrist watches of those days!), microwave transmitters (er, what about the mobile phones most youngsters now carry in their pockets?), static electricity generators and reactive chemicals. They were the things that excited me and instilled in me a love of science. How do teachers convey the excitement of science, if all the pupils can do is sit and watch?
Personally I am not surprised. What role models do our youngsters have? What is portrayed in the very media that bewail the lack of science students? It seems to me that the only role models portrayed are the sports personalities and the celebrities of the showbiz world. Whenever scientists appear, they are often portrayed as badly dressed, speaking words that most people do not understand and frequently lacking in social graces.
Also, perhaps, our concern for the safety of the pupils in schools has led to the curtailment of many experiments in classrooms. Science is now seen by many as 'boring' as much content is conveyed by watching videos. Gone are the times when pupils were let loose with geiger counters and radioactive materials (even though they were less active than the luminous paint used in the wrist watches of those days!), microwave transmitters (er, what about the mobile phones most youngsters now carry in their pockets?), static electricity generators and reactive chemicals. They were the things that excited me and instilled in me a love of science. How do teachers convey the excitement of science, if all the pupils can do is sit and watch?
Monday, 20 August 2007
Marriage is like team work
One of our team left for his annual holiday the other day. Except that it is actually his wedding and honeymoon. As my wife and I have just celebrated our wedding anniversary, it put me to thinking about marriage in these modern times.
Our team had a monthly meeting and the team leader, when asked to nominate the best worker in the team, said "everyone". I had to think a bit about that, as we are so used to picking on one individual that we have elevated it to the "cult of the celebrity" and forgotten, in my view the need for true team working.
Marriage and team work are quite similar in many ways. Both take individuals who have different abilities and outlook on life and put them to working together. In each case, the individuals must learn to sacrifice part of themselves in order to achieve something greater. Otherwise the team will not survive. The common term today is "my partner", but married couples are partners too. In marriage, though, the partnership is made within a very public commitment.
Our team had a monthly meeting and the team leader, when asked to nominate the best worker in the team, said "everyone". I had to think a bit about that, as we are so used to picking on one individual that we have elevated it to the "cult of the celebrity" and forgotten, in my view the need for true team working.
Marriage and team work are quite similar in many ways. Both take individuals who have different abilities and outlook on life and put them to working together. In each case, the individuals must learn to sacrifice part of themselves in order to achieve something greater. Otherwise the team will not survive. The common term today is "my partner", but married couples are partners too. In marriage, though, the partnership is made within a very public commitment.
Saturday, 11 August 2007
Capacity planning
Two news items caught my attention this week. One of them was a report of a court case in America where, if I understood correctly, internet providers were being asked to keep a copy of every email and web page that passed through their systems. This put me to thinking about what that would mean in storage requirements. You see, testing a program does not just mean checking that the right text, icons and graphics are displayed, and clicking an icon performs the required action. Non-functional testing is looking at reliability, speed, and capacity.
So I started to think what is the storage requirement if an internet provider held a copy of all their traffic.
For one small provider with just two 64Mbit links, assuming that those links are mainly for business users (that is, traffic mostly between 8am and 6pm) with the links at just 75% of their capacity, then in one week the total traffic would be 64 * 0.75 * 3600 seconds in an hour * 10 hours * 5 days in Megabits. That comes to 8640000 Megabits (864 Gigabytes) per week. Of course, if the provider has a few hundred or thousand individual subscribers, each downloading emails, software and music files, and browsing the web looking for maps, video clips, reading and contributing to blogs, and so on every night then that figure could easily rise to double or triple that original estimate of 864Gb per week. Taken over the course of a year it approaches something of the order of 100 TerraBytes required for the storage.
If that is the figure for one small internet provider, just stop to think what the storage requirements will be for some of the larger providers who count their customers in the hundreds of thousands.
As you can see, bandwidth capacity and storage are important points to consider in planning any new service, or when upgrading an existing one.
So I started to think what is the storage requirement if an internet provider held a copy of all their traffic.
For one small provider with just two 64Mbit links, assuming that those links are mainly for business users (that is, traffic mostly between 8am and 6pm) with the links at just 75% of their capacity, then in one week the total traffic would be 64 * 0.75 * 3600 seconds in an hour * 10 hours * 5 days in Megabits. That comes to 8640000 Megabits (864 Gigabytes) per week. Of course, if the provider has a few hundred or thousand individual subscribers, each downloading emails, software and music files, and browsing the web looking for maps, video clips, reading and contributing to blogs, and so on every night then that figure could easily rise to double or triple that original estimate of 864Gb per week. Taken over the course of a year it approaches something of the order of 100 TerraBytes required for the storage.
If that is the figure for one small internet provider, just stop to think what the storage requirements will be for some of the larger providers who count their customers in the hundreds of thousands.
As you can see, bandwidth capacity and storage are important points to consider in planning any new service, or when upgrading an existing one.
Thursday, 2 August 2007
Back in the thick of it
Or should that be, back in the thick of *I.T.* ? I have been away from all things technical for the last two weeks - mostly walking, with a bit of surfing and swimming. Leave behind the computer, the phone and all that sort of thing. "What is the weather going to be" was answered by "are there clouds or blue sky on the horizon"!
Sometimes it pays to see just how dependent we have become on technology. It seems many of us could not function at all without it. Of course, there are those like myself whose work is based on computers, whether that be administering them or programming them. I am thinking more of how we seem to 'need' technology for entertainment. Gone are the days for most people (did they ever exist for some?) of gathering together to talk, tell stories, sing or dance, or enjoy walking in the countryside.
In a couple of weeks I am taking our family to an Open Air concert, complete with full orchestra, singers and a firework finale. We shall go with a picnic meal and (given that this is England in summer) raincoats.
I will 'escape' to the country whenever I can. How about you?
"The city is the home of the body but the country is the home of the soul" (Baha'i writings)
Sometimes it pays to see just how dependent we have become on technology. It seems many of us could not function at all without it. Of course, there are those like myself whose work is based on computers, whether that be administering them or programming them. I am thinking more of how we seem to 'need' technology for entertainment. Gone are the days for most people (did they ever exist for some?) of gathering together to talk, tell stories, sing or dance, or enjoy walking in the countryside.
In a couple of weeks I am taking our family to an Open Air concert, complete with full orchestra, singers and a firework finale. We shall go with a picnic meal and (given that this is England in summer) raincoats.
I will 'escape' to the country whenever I can. How about you?
"The city is the home of the body but the country is the home of the soul" (Baha'i writings)
Wednesday, 11 July 2007
Requirements Gathering
Requirements gathering is the first step on the "traditional" process of designing any new piece of software, and involves asking detailed questions regarding what the expected users of the system want to see in the finished product.
I have found, working as a systems or process analyst for some years, is that the end users rarely have a clear view of what they want and certainly not in precise details.
I have worked with many people over the last 40 years and I would put them into two broad groups - those that go for the "details" and those that go for the "big picture", or "helicopter view" as one Managing Director once described it to me.
Computer programmers tend to be in the "details" group, whilst managers tend to be in the "big picture" group. This is just by the very nature of the jobs, they attract people with that type of view. Of course, neither view is any better than the other, as both are needed.
The difficulty for requirements gathering then, is that of getting the requirements in enough detail to allow the programmers to write the code, without the managers or end users losing patience or retreating from the project.
I am prompted to muse on these thoughts as I prepare to become involved in "SCRUM" and Agile.
I have found, working as a systems or process analyst for some years, is that the end users rarely have a clear view of what they want and certainly not in precise details.
I have worked with many people over the last 40 years and I would put them into two broad groups - those that go for the "details" and those that go for the "big picture", or "helicopter view" as one Managing Director once described it to me.
Computer programmers tend to be in the "details" group, whilst managers tend to be in the "big picture" group. This is just by the very nature of the jobs, they attract people with that type of view. Of course, neither view is any better than the other, as both are needed.
The difficulty for requirements gathering then, is that of getting the requirements in enough detail to allow the programmers to write the code, without the managers or end users losing patience or retreating from the project.
I am prompted to muse on these thoughts as I prepare to become involved in "SCRUM" and Agile.
Monday, 9 July 2007
Energy saving, who me?
So, the Live Planet concerts have come and gone, with all the controversy regarding the 'carbon footprint' of the participants. However, I don't think that was the point. It has made people think more about energy consumption, conservation and so on.
Of course, those of us who surround ourselves with technology use quite a lot, so who am I to talk of energy saving? After all, I have a network of computers at home and all the other usual gadgets. Well I regularly switch off all the devices that are not in use. But that is nothing to do with any new "green movement", it is the way that I was brought up by my parents. I travel by public transport whenever I can (every day to work, apart from when I cycle), have energy saving bulbs throughout the house, and recycle all paper,cardboard, tins and plastic.
Some time ago, I replaced the old computer that was running my firewall (you do have a firewall, yes?). It's power consumption was concerning me, and the fan was getting noisy. So I went out and bought a new router device that has a 4-port hub and wireless device combined. Very easy to plug in and get going and it saves me having two separate devices (hub and firewall) as well as consuming over 300 watts less power.
Two laptop computers have replaced the desktop computers, again with a saving in power, and the family share one printer.
Will I get a new flat screen TV? Nah, they are wasteful on power and would only see my electric bill rise again. Now, a combined DVD and video player, that is a thought. Let's get the booklets out and see their power consumption. can I save anything by getting one device to replace the two of them?
"Be anxiously concerned for the age in which you live and centre your deliberations on its exigencies and requirements" (Baha'i Faith)
Of course, those of us who surround ourselves with technology use quite a lot, so who am I to talk of energy saving? After all, I have a network of computers at home and all the other usual gadgets. Well I regularly switch off all the devices that are not in use. But that is nothing to do with any new "green movement", it is the way that I was brought up by my parents. I travel by public transport whenever I can (every day to work, apart from when I cycle), have energy saving bulbs throughout the house, and recycle all paper,cardboard, tins and plastic.
Some time ago, I replaced the old computer that was running my firewall (you do have a firewall, yes?). It's power consumption was concerning me, and the fan was getting noisy. So I went out and bought a new router device that has a 4-port hub and wireless device combined. Very easy to plug in and get going and it saves me having two separate devices (hub and firewall) as well as consuming over 300 watts less power.
Two laptop computers have replaced the desktop computers, again with a saving in power, and the family share one printer.
Will I get a new flat screen TV? Nah, they are wasteful on power and would only see my electric bill rise again. Now, a combined DVD and video player, that is a thought. Let's get the booklets out and see their power consumption. can I save anything by getting one device to replace the two of them?
"Be anxiously concerned for the age in which you live and centre your deliberations on its exigencies and requirements" (Baha'i Faith)
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