[email protected] (Joel C. Ewing) writes: > If the hardware knows it has incomplete information to write an entire > block because of some abnormal hardware condition, then something should > be done to guarantee that any later attempt to read that block will > produce an error indication. If that is not the case, this would appear > to be a violation of one of the major tenets of mainframe design: that > any data errors resulting from hardware issues should be at least > detectable, if not correctable. Writing a "valid" block with trailing > zeros in such a case sounds a bad design decision.
re: http://www.garlic.com/~lynn/2014k.html#7 Fwd: [sqlite] presentation about ordering and atomicity of filesystems http://www.garlic.com/~lynn/2014k.html#8 Fwd: [sqlite] presentation about ordering and atomicity of filesystems *and* generating a valid error correcting code for the propogated zeros at one point i was asked to audit some of the early raid5 vendors ... and there were some cases where i had to give presentations on what "no-single-point-of-failure" means (having found single points of failure). nearly decade earlier, i was involved in working with NSF on interconnecting NSF supercomputer centers (later evolves into the NSFNET backbone, precursor to the modern internet) ... some old email http://www.garlic.com/~lynn/lhwemail.html#nsfnet in part because had internal (HSDT) project with T1 (1.5mbit/sec) and faster links ... some past posts http://www.garlic.com/~lynn/subnetwork.html#hsdt one of the people working on the effort had been graduate student of Reed at jpl/caltech and did a lot of the original work on reed-solomon (error correcting code). Also got to work with cyclotomics up in berkeley (on of the founders was berlekamp) ... cyclotomics did a lot of the reed-solomon stuff that shows up in the cdrom standard ... during this period, they were bought by kodak. a couple recent posts http://www.garlic.com/~lynn/2014g.html#75 non-IBM: SONY new tape storage - 185 Terabytes on a tape http://www.garlic.com/~lynn/2014j.html#68 No Internet. No Microsoft Windows. No iPods. This Is What Tech Was Like In 1984 reed-solomon http://en.wikipedia.org/wiki/Reed%E2%80%93Solomon_error_correction as previously mentioned ... one of the justifications for the industry moving from fba-512 to fba-4096 was reducing space taken up by error correcting code: http://en.wikipedia.org/wiki/Advanced_Format past posts mentioning fba, ckd, multi-track search, etc http://www.garlic.com/~lynn/submain.html#dasd -- virtualization experience starting Jan1968, online at home since Mar1970 ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
