Re: Informix vs. AIX Mirroring

In article <52iq0b$fgi@news.interlog.com>, John Morton <mortonj@interlog.com> writes >Hi there. We're just moving from a RAID5 box onto some SSA disk, so we >have to think about mirroring. Informix recommends Informix mirroring, >and IBM recommends AIX (what a shock!). We are running AIX 4.1.4 and >Informix 7.20 on an 8-way RS6000. > >Seems to me that AIX mirroring on a JFS would be easier to manage than >Informix mirroring and raw space, but I'm worried about performance >.. it's a busy oltp application. > >Any ideas or opinions? > >John Morton >mortonj@interlog.com > The word from the tutor on my Informix Performance Tuning course last summer said he has actually looked tried internally in Informix to find out whether Informix mirroring is better than UNIX mirroring in terms of performance. The answer was ' I can find nothing which indicates anything either way'. Seems like Informix provided it so you could use it If the operating system does not support mirroring. ALso another tick on the list of features a 'good' database server provides and relatively easy to implement. UNIX mirroring is normally done using a Logical Volume Manager. This can also provide useful features such as making 2 disks look like one big one. Making 1 big disk look like 2 disks etc. So it is more flexible and you may as well let it do the mirroring as well. SO...use UNIX mirroring if available otherwise use Informix's mirroring. -- David Williams