Database And Brain

Inspired by Haruki Murakami, the unique novel writer, we just launched a new blog, which is like an essay "Katakana" dictionary.

We have three types of words in Japanese. Kanji(漢字), Hiragana(ひらがな), and Katakana(カタカナ). Katakana represents sounds, mostly of foreign words like Coca Cola(コカコーラ).

One Katakana word a day. Then, one guy writes an essay related to the word. Interesting, isn't it.

Here's the dictionary. Enjoy!
http://ameblo.jp/teamharukist/

I love Jazz, and so to play trumpet.

I don't like to manage nor to be managed.

I love OpenSource mind like hippy's.

I love objects.

But the problem is, they are not so successful in Business.

Okay. Let me think. Why?

...

It is only me that enjoys?

That could be a reason.
But rather, it would be a mandatory to succeed.

The reason is, perhaps, the lack of attitude for audience/end users.

Playing trumpet is a part of my life, even myself.
So, that would be great if audience get high/relaxed,
but that's not the first thing.

Object? That's for my business.

Object fundamentalism? I don't think I am, but some think I am.

Cache, an ultimate enterprise object-capable database.
db4o, an open source object database for embedded system
Rational, needless to say

The Object Fundamentalism family got a certain level of success.
But it seemed to be limited so far.

Why?

Through other businesses, I realized that
a successful technology can provide end users with benefits directly.
Oracle, Google, VMWare, Salesforce.
And they have lots of believers who brings the bible to end users
to integrate, convince, pray and sell.
Sometimes, those believers put some benefits on top of it,
but even without it, the bible itself is valuable.

What about Object Fundamentalism family?

It depends on engineers.
That means a value is created *by engineers* for their customer.
So, the point would be to hire a great engineer rather than a product.

The Object Fundamentalism itself is worse than a piece of bread for end users.

How to improve the situation?

A product/service should have a clear benefit for end users, not (only) for engineers.

For end users, object words are as good as, with Japanese old saying, Buddha's words to a horse.

- I found an interesting story from "Essential Drucker".

The three stonecutters who were asked what they were doing. The first replied, "I am making a living." The second kept on hammering while he said, "I am doing the best job of stonecutting in the entire country." The third one looked up with a visionary gleam in his eyes and said, "I am building a cathedral."

The third man is, of course, the true "manager." The first man knows what he wants to get out of the work and manages to do so. He is likely to give a "fair day's work for a fair day's pay." It is the second man who is a problem. Workmanship is essential; without it no business can flourish; in fact, an organization becomes demoralized if it does not demand of its members that most scrupulous workmanship they are capable of. But there is always a danger that the true workman, the true professional, will believe that he is accomplishing something when in effect he is just polishing stones or collecting footnotes. Workmanship must be encouraged in the business enterprise. But it must always be related to the needs of the whole.

My latest column, titled "Lying Computer" was up today.

It's about "sync", which flushes buffers in memory and write to disk physically, then synchronized the state in memory with one on file. It is not done by one single component, but done in relay. It should work as expected, but won't often today. So, who's telling a lie?

A couple of years ago, not sure, but there certainly were some hot topics about disk write back cache.

Linux: Should disk write cache be disabled for any journalised filesystem?

Windows: Manually Enable/Disable Disk Write Caching

In the Windows manual, the latter one, you'll see a clear description.

By enabling write caching, file system corruption and/or data loss could occur if the machine experiences a power, device or system failure and cannot be shutdown properly.

So, it is natural to disable the write cache by default, from the database vendor's point of view.

But today, disk write back cache is enabled by default. Often, you can not even get a way to disable it. This is for the sake of performance because of the Coelacanth, HDD, in computer.

What makes it worth is an emergence of some kind of virtualization like Java and .NET.

sync
public void sync() throws SyncFailedExceptionForce

all system buffers to synchronize with the underlying device. This method returns after all modified data and attributes of this FileDescriptor have been written to the relevant device(s). In particular, if this FileDescriptor refers to a physical storage medium, such as a file in a file system, sync will not return until all in-memory modified copies of buffers associated with this FileDesecriptor have been written to the physical medium. sync is meant to be used by code that requires physical storage (such as a file) to be in a known state For example, a class that provided a simple transaction facility might use sync to ensure that all changes to a file caused by a given transaction were recorded on a storage medium. sync only affects buffers downstream of this FileDescriptor. If any in-memory buffering is being done by the application (for example, by a BufferedOutputStream object), those buffers must be flushed into the FileDescriptor (for example, by invoking OutputStream.flush) before that data will be affected by sync.

Throws:
SyncFailedException - Thrown when the buffers cannot be flushed, or because the system cannot guarantee that all the buffers have been synchronized with physical media.
Since:
JDK1.1

.NET: FileStream.Flush not flushing?

FileStream.Flush Method
Clears all buffers for this stream and causes any buffered data to be written to the file system.

Stream.Flush Method
When overridden in a derived class, clears all buffers for this stream and causes any buffered data to be written to the underlying device.

Microsoft Windows CE .NET 4.2
FlushFileBuffers
This function clears the buffers for the specified file and causes all buffered data to be written to the file.

Copy CodeBOOL WINAPI FlushFileBuffers(
HANDLE hFile
); Parameters
hFile
[in] Handle to an open file. The function flushes this file's buffers. The file handle must have GENERIC_WRITE access to the file.
If hFile is a handle to a communications device, the function only flushes the transmit buffer.

Return Values
Nonzero indicates success. Zero indicates failure. To get extended error information, call GetLastError.

Remarks
The WriteFile function typically writes data to an internal buffer that the OS writes to disk on a regular basis. The FlushFileBuffers function writes the buffered information for the specified file to disk.

Requirements
OS Versions: Windows CE 1.0 and later.
Header: Winbase.h.
Link Library: Coredll.lib.

Then, unless you are aware of hardware and its underlying architectures, innocent Java/.NET guys would be misled.

I will check some major langurages/OSes how they describe its sync behavior, and then ask to fix or put a warning if necessary.

The next question is what is the best workaround for you. I will write it in my next column.

I'm just launching my business site.

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