Re: HELP - Hardware mirroring versus dbms mirroring

> Cathy Kipp (ckipp@vth1.vth.colostate.edu) wrote: > : Joe Lumbley writes: > : -> > : ->Hardware mirroring is usually best, as it's faster. Next is HP-UX. > Last: ->comes OnLine mirroring. OnLine mirroring contains a little bit > of logic: ->regarding how to handle chunks that are down, but with any > luck the HPUX: ->or hardware mirroring will never let OnLine see that > situation anyway. > > : Joe, > > :Not to disagree with an expert, but I think it's important to mention > here that:while hardware mirroring may be faster with the OnLine engine, > under the 6.0: DSA engine, Informix miroring will offer some performance > advantages. > > : Regards, > > : - Cathy > > > Cathy, > > Disagreeing with me about mirroring is NOT disagreeing with an expert! > :v) > > Especially about 6.0. What performance advantages do you know about in > the Informix mirroring in 6.0? From 6.00 if you have a query joining two tables and are using mirroring, OnLine will read one from the primary and the other from the mirror chunk, thereby potentially saving disk head movement (the slowest operation inside a database). Try doing that with hardware mirroring! akent@cix.compulink.co.uk (Andy Kent) -------------------------------------