large files systems & SE
Posted in 1994
Topics: General Discussion
We are running Informix SE, version 5.01 on a Sun SPARC IPX, running SunOS 4.1.3. We have a database that will soon grow beyond 2GB. The individual tables within the database will not exceed 2GB, just the total size of the database. In order to accommodate this we've bought an 8.4 GB drive from Acropolis (actually 4 2.1 GB drives) and are using Sun's DiskSuite to stripe them together. In days gone by SunOS restricted the filesystem size to 2GB. The use of DiskSuite sidesteps this restriction. Actual files are still restricted to 2GB, per Unix definition. The manual that comes with DiskSuite states on page 9-2: 1) Programs that use the raw device interface beyond two Gbytes to access file system information must be rewritten to use "lseek2(3)" in place of the "lseek(2V)" system call. "lseek2" is a library function provided with DiskSuite. It is similar to "lseek(2V)", but it uses a 64-bit file offset instead of 32. 2) Secondly, programs that call "statfs(2)" or "fstatfs(2)" must take care to avoid integer overflow when doing calculations involving the file system size or free space. The system calls return this info- mation in units of the fundamental file system block size, normally 1024 bytes. Some programs convert the numbers from blocks to bytes before calculating. For file systems larger than two Gbytes, this may cause integer overflow. Such programs should be modified to calculate in block-size units instead. -------------- Is SE going to collide with this? If push comes to shove, we can partition our database up into several databases, or use symbolic links, or some other strategy to make things work, but I'd prefer to move Informix over the new striped device and treat it as one big disk. Am I going to get lucky on this one? You can post replies, or send them directly to: brent@heart.cor.epa.gov. Thanks in advance. ________________________________________________________________________ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ On a certain occasion when Father Nicanor brought a checker set to the chestnut tree and invited him to a game, Jose Arcadio Beundia would not accept, because according to him he could never understand the sense of a contest in which the two adversaries have agreed upon the rules. -- Gabriel Garcia Marquez, _One Hundred Years of Solitude_