Because of the manner in which the write subsystem was implemented, it is NOT a trivial task to either pre-detect or recover from a system write failure, which is usually the cause of the corruption. The group structure (which will be comprised of one or more buffers) is modified in memory, and then shipped off to the system for writing; there is no way to determine if in fact any particular write actually made it TO disk. If a write() operation returned successful, then that is the only validation we can check; if the system burps on that buffer later down the chain, there is no way to detect that. Having spent better than 10 years in the file system, there was serious discussion of how to do this, but unfortunately required a very serious rewrite of the write subsystem; obviously, that work would never be done. The various recovery tools shipped with the product do a pretty decent job of recovering as much of the file as possible.
Hope this helps. ______________________________________________________________________ From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of "Stevenson, Charles" <[EMAIL PROTECTED]> Sent: Wednesday, September 28, 2005 8:10 AM To: <[email protected]> Subject: FW: [U2] Blink Error - Backward Link error Do I detect an enhancement suggestion? Whether this is trivial or hard is beyond me, but I tend to believe Mr. Phillips. (On this subject, anyway. I don't know his opinion of the British Royals, for example.) cds -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Martin Phillips Sent: Wednesday, September 28, 2005 1:11 AM To: [email protected] Subject: Re: [U2] Blink Error - Backward Link error Why, oh why, doesn't UV fail the write before it corrupts the file? It is trivial to know that this is about to happen. Martin Phillips Ladybridge Systems 17b Coldstream Lane, Hardingstone, Northampton NN4 6DB +44-(0)1604-709200 ------- u2-users mailing list [email protected] To unsubscribe please visit http://listserver.u2ug.org/ ------- u2-users mailing list [email protected] To unsubscribe please visit http://listserver.u2ug.org/
