Mike Ault's thoughts on various topics, Oracle related and not. Note: I reserve the right to delete comments that are not contributing to the overall theme of the BLOG or are insulting or demeaning to anyone. The posts on this blog are provided “as is” with no warranties and confer no rights. The opinions expressed on this site are mine and mine alone, and do not necessarily represent those of my employer.

Saturday, March 26, 2005

Lack of Compassion?

I recently read an article in Utne magazine (online at http://www.utne.com/) entitles "Dying for Lobster" that, as a diver left me horrified. For those of you who aren't divers, when you dive and breath air under pressure, more than normal amounts of nitrogen are forced into your blood, as long as you dive within proper limits and follow proper safety, this nitrogen comes back out without causing problems. However, if you push the limits, don't follow safety rules (for example, staying down to long and ascending to fast) then the nitrogen comes out too fast, like bubbles of gas in a soda can. The gas is likely to come out at joints and as a rash at the surface of the skin. Oh, it also comes out in the brain and spinal cord, causing stroke like symptoms and paralysis. This is called decompression illness, you may have heard it called "the bends." If you are rushed to a decompression chamber the symptoms in many cases can be reversed, although there can be residual side effects.

Anyway, the article talked about Nicaraguan divers who dive for lobster from lobster company boats. These divers dive with poor equipment, no depth or pressure gage, no dive computers. They may dive 15 or more times a day to depths of 120 feet or more. I am sure they are encourged to bring up as many lobsters as they can each day. This means they ignore bottom time limits (if they are even taught them) and ignore safe ascent rates (again if they are even taght them.) As a result many of them "get bent" and unfortunately, since these boats are out for 2-3 weeks, don't get the benefit of getting taken to a deco chamber until it is too late. This results in many being crippled for life and many die.

On a Scuba board I suggested setting up a donation center for used dive equipment that is still servicable. Most of this equipment moulders away in closets, or is sold on ebay for a fraction of its worth. Since there is already a tax-exempt group set up to provide deco chambers for the divers I thought we could probably set up with them to provide tax receipts (at least to USA divers) for donated equipment that they could then use for reducing their taxes. The Nicaraguan divers win, we win. We would also provide training manuals and training to help these divers understand how to avoid the injuries from bends and how to use the more complex dive computers.

I understand that this is not correcting the problem, the exploitation of the workers and a government that doesn't care, but we really can't do much about that. We can make these divers safe divers and ease or prevent their suffering. To a response, all responses on the Scuba board were negative. No one saw the benefit of helping the divers, no one offered spare equipment.

Several of the more vocal respondents were from Canada, and I thought Canadians were a warm, friendly people who wanted to help others. Most were from the USA. I thought there would be more compassion for the plight of these divers, I thought there would be more generosity. I was wrong.

One diver said Red Lobster was the number one purchaser of the lobsters, I haven't confirmed that, nor do I know how to confirm it, if someone could I would appreciate it. Anyway, would a boycott help? The main reason the divers there dive is for the money. For 2-3 weeks of 15 dives a day and risking their health and lives they make $300.00 and room an board. Now for their economy this is good money, right up to the point where it kills them. In a boycott, if it was 100% successful, would it help these divers? It might eliminate their livelihood and throw them back into abject poverty, I am sure they would thank us. Through education and the provision of better equipment we would improve the quality of their lives, and as a side effect, reduce the pressure on the lobster population as limiting bottom time would reduce the number taken.

I hate to think the divers may have been motivated by the thought that they could get more money for the used equipment by selling it rather than donating it. I also hate to think they are so naive as to think we could change the government there and make it more compassionate (haven't we spent billions to do that with no visible affect?.) I also hate to think they care more about lobsters than they do men.

Tuesday, March 22, 2005

Stray Thoughts

It is amazing the things that come to mind just as you are drifting off to sleep. Old memories, new thoughts, the answer to that annoying question. I guess it shows that the mind is continuously at work processing things that we see and hear, sometimes long after we have stopped thinking about them on the surface.

Last night for example religion for some reason was paramount in my mind as I started to drift off. I remembered such adages as "God helps them that help themselves", and the parable of the servants and the money which goes something like "A master gave three servants each some money and instructed them to take care of it while he was gone. One went out and invested it, another used it to buy grain and plant it, while the third buried it. Upon the masters return each was called into accounting for the money they had been given, the first gave back two fold, the second was unable to give back crops because of a blight, the third gave back exactly what he was given. The master praised the two who had invested and put the money to work and rewarded them, even though the second had lost the money, the third, who only hid the money to return the exact amount, was punished." forgive any paraphrasing...

It seems to me that many of the fundamentalist beliefs are rather like the third servant. They take the coin of heaven and attempt to return it without changing it, improvement or loss. They feel that to question, challenge or add to the amount given (I am not talking about how many you add to the numbers of the church, I am talking about knowledge) is in some way forbidden, as if the holy book sprung, not from the labor of hundreds of people over thousands of years, but whole and perfect from the hand of God. When there are errors in translation, errors in usage, errors in understanding, they accept this all as whole cloth, not weaving more, not patching the holes, and not washing the stains away.

This happens of course not only in religion, but in life as well. In technical areas we have our own version of the GI-GO syndrome (garbage in - garbage out) known as garbage-in-gospel-out (I talked about this in an article back in the late 80's), that portends if it issues from a computer it must be gospel. In law we base everything on precedents, as if those in the past were smarter, more enlightened and knew more about the current situation than we do.

I believe that each person has the responsibility to learn as much as they can. We are all our own product. Many times people have accused me of being, shall I say eclectic? To which a say thanks. Having read at last estimate over 3000 or so books in my lifetime (give or take 100 or so) and hoping to read at least another 3000 before I pass into my reward, I find it gives me quite a platform on which to stand while I reach for more. Reach for more understanding. more knowledge and more insight that is. My reading reaches from technical and religious books to science fiction, historical fiction and the occasional horror or action adventure. Each book has something to teach, if you limit your reading on any topic to just one author, your horizon will be limited.

In a recent conversation someone dear to me expressed horror that I would read certain books by authors who disagreed with that persons basic belief structure. Words are only given power by the reader. I read what gives me more understanding, for it is only in understanding something can we elevate or overcome it.

Well, enough rambling for one day, there is work to be done!

Sunday, March 20, 2005

Be Careful In What You Prove

I have recently been researching scuba diving sites within the USA for a possible series of articles for a scuba magazine. Believe it or not, I do have interests outside of Oracle! One of the sites, Rock Lake, Wisconsin is of particular interest for what lies beneath its turgid waters. But if I reveal too much now it might dilute the future article. What it has brought to light is the fact that you must be careful not only in what you believe to be true but in what you prove to be true. The tales of what lay beneath Rock Lake vary from lost Atlantis to only legends. I am sure if the two camps were brought together, bloodshed would ensue as each defended their point of view. To each of the camps, what they believe is the truth.

Many people believe that truth is immutable, that what is true now is always true. However, times change, technology changes, even (especially) theology. It was not so long ago that respected scientists believed that a Doctor washing his hands was not professional, that travelling at speeds in excess of 30 miles per hour would do irreperable damage to the human frame, that travelling faster than the speed of sound would result in a crash much like hitting a brick wall, or that setting off an atomic bomb would ignite the atmosphere and annilalate mankind.

Of course all of the above has been proven incorrect. Now there are those that propose that the charished notion that the speed of light is absolute is also a myth that will be dispelled with time (believe it or not, the "warp" drive of Star Trek fame has a basis in theoretical physics, of course it requires more energy than we can currently produce, but in medevil times wouldn't all of our current technology give us a one way ticket to the witches bonfire? ) however, as much energy as we can currently produce is perhaps a far cry from as much energy as we can produce. Some go as far as to claim that some super-novas are proof that some technologies lost control of zero-point energy.

So also must we view "proofs" given of things that are acceptable incurrent technology, in Oracle and in other technologies, as only transient in nature. Watch out that the "proofs" of today don't become tomorrows old wives tales.

For example, it wasn't too long ago that separation of indexes and tables in databases was a good and accepted method for improving performance. Of course this was because otherwise they would be on the same disk platter if they weren't seperate and would conflict. Now of course with the almost universal implementation of RAID techology (rendundent arrays of independent/inexpensive disks) this becomes unneeded (sometimes, depending on the amount of data stored on each disk in the array). It could be demonstrated, when they shared a single disk, that moving indexes away from tables improved performance. Based on that proof, no longer valid, some will say that moving indexes away from tables always improves performance.

Likewise the old saw that moving to RAW devices in UNIX (raw meaning the application was responsible for IO) would result in large improvements in performance. This of course was based on the premise that all of the buffering in the OS for non-raw filesystems caused delays. Now modern file systems can be set to eliminate this buffering and journalling delays and the performance gains from raw have deminished to nearly null. Of course rebuilding the objects within the databases involved, (tables and indexes) restoring them to proper parameters that they may have exceeded through years of neglect also helped.

So now we have a new crop of experts providing proofs (sometimes limited to a single-user, small database on a laptop) that their methods are the best and no doubt their proofs will be sited long after they are useful or meaningful and their expert advice will fade into old DBA tales as new technologies and methods become the rage. This is as it should be.

I guess I am trying to say, in a rambling way, that todays sage advice becomes tomorrows old tale. We must all be aware of what the current methods are, realize when the old methods no longer apply, and gracefully accept new ways if we are to grow and prosper. However, we must also recognize when the "proper" method evolves and mutates into a "new" method, leaving the old ways to die away.

So be careful in what you prove and how you prove it. What seems clever today may come back to haunt you. You may be aplogizing several years down the road for what is right now, but not in the future. The net is an amazing place. No doubt you can find numerous places where I may have exponded on the virtues of separation of indexes and tables, on rebuilding indexes frequently or other items that have since been proved, for current versions, old DBA tales. I like others before, am not immune to time and neither is my advice.

If any paper you read is older than a year or two, I suggest you take its advice with a big grain of salt as it may be applicable only to history and not current events.

Critics love to dig up old papers, presentations and advice given and use it to bludgeon people into believing they are the only authority. Take this type of advice with a grain of salt as well. In time, their advice will be referenced, out of date and out of style.

Wednesday, March 16, 2005

Call me Abused

Just finished doing a RAC class on Oracle9i RAC. During the class we installed Oracle RAC. Let me tell you, installing RAC on Oracle9i, version is not the funnest thing I have done in a long time. Feel like a horse that was rode hard and put down wet. When I first started working with 9i and RAC the install was a bit convoluted. However, it has gotten much worse! Between missing directories, missing links, needing to install the universal installer, having the universal installer mess up the JRE, well, you ge the picture.

Compared to this "terminal" 9i release, 10g RAC install is a snap. But enough about that. Some comments on classrooms. Always teach from the front, it allows eye contact and allows you to see the expressions on the classes faces. I have had to teach three times from the back of a room, in each case I left feeling that I didn't do a good job, usually, so did the class. Eye contact and being able to see if the class understands key points is critical to good teaching.

Also, if the class uses software, such as RAC, make sure it is up and running before the class begins (unless the major part of the class is the install). The other times I have felt that the class got less from the class then they should have when I had to wrestle with a balky install. No matter why the software doesn't install, be it poor documentation, bugs or just bad karma, this will rub off on the classes opinion of your expertise.

A final observation, try to reduce any powerpoint slides to just talking points and needed diagrams. If you have a whiteboard, use it. Classes like the hands-on approach. As tempting as it is sometimes, especially when facing outside issues such as a balky install, don't just read the slides! I find myself falling into the trap when I have not had sufficient time to prepare for the class (it usually takes 4-6 hours per hour of class time to prepare materials.) Usually this means I put too much on the slides. By just putting bullet points for the topics on the slides, you can avoid this trap.

Well, that is all for now, talk to you later.

Tuesday, March 15, 2005

It is Totally Amazing...

I will begin blogging with a few thoughts on the time and energy other "experts" put into questioning everything said. I find it amazing the folks such as Howard J. Rogers can spend so much time and energy beating dead topics to death. Most of us have moved beyond arguments about index rebuilding and coalescing. I suggest them when it is indicated that it will help, it is one tool in a tuning experts arsenal. When I suggest a rebuild or a coalesce of an index in Oracle database systems it is only after a complete analysis points to the index as a problem.

Business must be slow down under for Howard to have so much free time. I have to grab a few minutes between running for the plane, working with customers all across the country and trying to keep up with my remote monitoring and tuning committments to swat at this annoying gadfly.

As to the whole debate (well, at least from Howards viewpoint it is a debate, for me it is just a tool to use when indicated) about reordering a column order in a concatenated index, again, Howard and others seem to feel that once an index is created it is sacred and can't be touched. Obviously they have never worked with a poorly crafted, poorly indexed third-party or custom generated application, for that matter, they must have never worked with Oracle's own Applications. I have seen applications where a table had 29 indexes. If I followed Howards way of thinking each would be a sacred object that I shouldn't touch because obviously the need for each was carefully considered and it would bring down the entire application to change it. Hog wash.

It merely shows that Howard spends too much time with theory and not enough in real-world tuning situations. I have been at over 24 client sites in the last 6 months doing tuning, optimizing and database evaluations. I find things that work and apply them as needed. My job is to help an ailing database back to health and to improve peformance of client applications. If this means that I drop, rebuild or otherwise change an index, then that is what it means. Heaven forbid, I even suggest adding an index occasionally!