Re: Informix indexes

Albert wisse wrote: > > I have to decide to mirror the indexes yes or no. If I don't mirror > the indexes then I can use two disks for the indexes to increase the > performance. > The thought behind is that if a disk with indexes chrashes then it is > simple to regenerate > the indexes in another dbspace. > I this approch valid or is it better to miror the index disk/dbspace > and so why. Performance may be a wash since the engine can read/write from both sides of the mirror simutaneously reading two independent index pages for the same gain you hope to get from fragmenting the indexes. You'll have to experiment, but I suspect that is what you will find and the safety of mirroring for your indexes which are at greater risk from crashes NOT related to disks than data pages are (due to the intimate linkages between index pages and between them and data pages) far outweighs any possible performance gain. Art S. Kagel