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[edit] talk

The page gives no reason why this practise is used. --Anonymous

I replaced this, and left out the specific programs mentioned because I could not find any mention of trouble porting those specific programs: "A common problem in computer programming is called word alignement. One way to increase performance, especially in RISC processors which are designed to maximize raw performance is to require data to loaded or stored on a word boundary. So though memory is commonly addressed by 8 bit bytes, loading a 32 bit integer or 64 bit floating point number would be required to be start at every 64 bits on a 64 bit machine. The processor could flag a fault if it were asked to load a number which was not on such a boundary, or call a routine which would effectively figure out which word or words contained the data and extract the equivalent value. This caused difficulty when the team from Mosaic Software ported their Twin Spreadsheet to the 68000 based Atari ST. The Intel 8086 architecture had no such restrictions. It would also cause difficulties in porting Microsoft Office to Windows NT on MIPS and PowerPC for NEC and IBM. Since the software was not written with such restrictions in mind, designers had to set a bit in the O/S to enable non-aligned data. However since this bit was masked with other flags, it was impossible to keep the O/S from faulting on non-aligned data when other modules used the other flags. This may have been a major factor in abandoning Windows NT on non-Intel processors as they failed as platforms for hosting common Windows applications and one more reason for the baffling dominance of the x86 architecture over technologically elegant rivals. "

I hope to have provided sufficient background, but I think the article still needs some work. (but I need to sleep)

Aij 07:03, 29 May 2006 (UTC)

[edit] Packed array

What is a packed array? It redirects here, but I could not find it. 85.145.103.163 (talk) 15:52, 30 January 2008 (UTC)

In the section Data_Structure_Padding, the article talks about that. 0x6adb015 (talk) 14:07, 3 March 2008 (UTC)

[edit] Too verbose/jargon filled

I'm a 4th year Comp Sci student sitting a PhD next year...and don't think the description here is clear enough. It really doesn't explain it in any useful way. I think a diagram, an analogy, or something similar would help. In its current state it's no use to anyone who isn't a computer expert-I come pretty close, and I can't follow it. It needs to be much, much, simpler at first, instead of jumping right into details. —Preceding unsigned comment added by 130.209.241.193 (talk) 11:53, 27 April 2008 (UTC)

I agree, one thing which struck is why is the word datum used instead of data? I've seen the word used before but needed to look it up, only to see that it's apparantly just a synonym to data, which is significantly more well understod. —Preceding unsigned comment added by 195.84.66.198 (talk) 13:31, 7 June 2008 (UTC)