Re^5: Generating a readline error

This sort of thing over not so reliable communication links is different than what I understood the question to be. I was watching one of my LWP programs yesterday and it bombed 4x in a row because the other site wasn't up. Things got sorted out and it worked. The application level stuff reconnects and tries again.

Here the question appeared to be me to formulated in terms of a disk file access. Maybe I got the wrong impression. I've worked on a number of very impressive IBM disk systems and I've never seen an application "retry" work because we give it the "full court press" when we know the data is important.

Anyway there is a big difference between: communication failed, bad packet, unable to connect, unable to authenticate, and "I've read some data but I know that is wrong, but before I use error correcting codes, I'm going to the best most consistent data that I can".

Anyway a sophisticated disk system has already done a complex series of 200 attempts before it says "I can't read the data". The IP communication layer is not that robust.

Comment on Re^5: Generating a readline error

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Re^6: Generating a readline error by JavaFan (Canon) on Jul 18, 2009 at 00:18 UTC
I don't really understand your post. Surely, you are not saying "cause the nifty IBM systems I worked with never give a read error, I cannot image anyone else getting one". I assume you realize not everyone has a nifty IBM system attached to his/her computer?	[reply]
Re^7: Generating a readline error by Marshall (Canon) on Jul 18, 2009 at 00:49 UTC
This is a misunderstanding. The disk system (hardware, micro-code on disk hardware, I/F board (hardware and also micro-code) in conjunction with O/S driver and O/S does a lot. I have a prototype IBM drive that after 11 years is failing. I lost a Seagate and a WD drive last year during a massive power failure. ALL of these sub-systems thing fail. I am not saying different. The question appeared to be "how to do I simulate a failure"? I tried to help with that question. All hard drives will fail. It is not "if". It is just "when". I tried to help simulate "when".	[reply]