Re: SE 5.10 UC1 Corruption

David Conn wrote: [SNIP] > Lately I have noticed a trend where two of the most volatile tables in the > system are being corrupted. This is also not an isolated incident and has > occured on 6 seperate occasions in as many sites over the past few months. > There does not seem to be a pattern as far as the platform is concerned > since today made the the spread even. > The symptoms are as follows : > -Corruption is detected after a daily batch extract of the tables is done, > the extract file does not pass routine checks and an exception is raised > with my support team. > -Bcheck confirms corruption > -An ls on the .dat and .idx file sizes reports a dat file in excess of 2GB > with a similar .idx file size. [SNIP] There's your culprit, the file is too big! Read on. > -How can the op`erating system report a file of this size? > -Since the size of the file reported by AIX is obvioulsy bogus, is AIX > itself being corrupted by Informix? [SNIP] No, I believe that AIX supports files larger than 2GB. However, Informix uses lseek and fseek to position within files and those functions only support files < 2GB (2,097,151 KB). Therefore the addresses of rows addressed beyond the 2GB size are wrapping and overwritting existing data and structures at the beginning of the files. Art S. Kagel