Talk:Legacy system

From Wikipedia, the free encyclopedia

Contents

[edit] Availability versus Reliability

Re: The phrase, "Extremely high AVAILABILITY." Should this not read, "Extremely high RELIABILITY?"

No, legacy systems aren't particularly reliable; components fail in them all the time. But if we're speaking of mainframe computers, they often contain massive amounts of redundancy so even in the face of a hard failure of some component or other, the system as a whole continues to be "available" for use. For example, they often contain N+1 (or better) power supplies so that one power supply can totally fail and the system keeps processing using the other "N" supplies. Within the CPU, the latest Z/OS processor chips contain two cores that operate in lock-step, executing the exact same instruction stream; additional logic compares the results between the two processors. If a mismatch is detected, the dilemma is kicked out to a service processor that decides which core got it right and resumes execution as if nothing had gone wrong. If a core continues to fail, the service processor masks it out and operation continues on just the one core. A clear failure has occurred and a service tech must eventually fix the system, but meanwhile, it's still fully available for use.
Atlant 00:20, 28 March 2006 (UTC)


Legacy systems - meaning code, operating system, software and hardware, are both extremely reliable and highly available. Generally speaking very stable after 30 or 40 years of refinement (the reason why they are still with us after that length of time), 'bugs' and down time are rarity, other than unusual data exceptions, and occasional hardware issues any technology will encounter after normal usage.

And, as for legacy code included in legacy system as terminology, you cannot have one without the other.

~Deborah~ —Preceding unsigned comment added by DeborahAH (talk • contribs) 21:52, 25 December 2007 (UTC)

[edit] Legacy system

One of the references points to a legacy system failing, instead of a new system failing. It should be replaced.

Yuhong Bao

[edit] Visual Basic References

Does anyone think that the references in the article to Visual Basic seem a little biased and bitter? I think VB has had it's name bashed by "real" programmers for years, but I am not sure that belongs in wiki. Just IMO.

Mfergason 21:28, 21 December 2006 (UTC)

Yes, bashing VB is a religious requirement for some people Pendragon39 01:00, 13 March 2007 (UTC)

[edit] Very bad style

Yes. All the mentioned shortcomings are evident. A more thoroughly biased, ill-informed, and incompetently written article is hard to find. Ideally, this deserves a full rewrite by an expert, for a change.

[edit] Proposed merge of legacy code with legacy system

  • Oppose merge; the two terms may have a hardware/software distinction. Robert K S 15:07, 15 June 2007 (UTC)

Oppose merger as legacy system can also refer to intelligent control systems,fire alarm systems,security systems etc. all of them hardware dependant —Preceding unsigned comment added by 82.15.254.6 (talk) 16:39, 4 September 2007 (UTC)

  • Oppose merge; I agree with Robert. The notion of a legacy system is an operational system concern. Legacy systems may be seen in a positive or negative light, but the implications for sustain-engineering are primarily around both failure scenarios and maintenance processes. The notion of legacy code is a software maintenance concern, and the implications for maintenance are primarily around the readability, extensibility, and adaptability of the code base, and the processes needed to refactor / rewrite the software as business needs change. --Nickmalik 17:32, 14 October 2007 (UTC)

[edit] awful article

This is an editorial, not an encyclopedic article. —Preceding unsigned comment added by 24.147.30.252 (talk) 14:48, 29 April 2008 (UTC)

[edit] Don't remove the 'alternate view'

I hate to start an edit war, but a previous editor made a huge change to the article with no discussion: he or she removed the "alternate view" section with a note stating that it is "awful." Perhaps that editor disagrees with the inclusion of this information, but removing it clearly makes the article one-sided and editorial in nature. I suggest a complete rewrite of the article with an attempt to keep it balanced. The term 'Legacy System' has a perjorative connotation, and it is entirely fair for the article to attempt to provide a balanced, non-perjorative, discussion. The entire article is awful. But removing that section simply makes it an awful-but-one-sided article. I do not find that to be better.

Please rewrite or discuss. --Nickmalik (talk) 18:32, 8 June 2008 (UTC)