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 Just to add fuel to the fire: HP's Logical Volume Manager will allow you to "stripe" non-array disks by creating extents on a rotating basis across multiple drives. This may/may not be advantageous as you develop a fragmentation strategy. If you use HP-UX mirroring, reads will be routed to the mirror copy if the primary is busy. Under heavy disk loads, this is very advantageous. _______ ________________________________________________________________ / / John Bria (SE) ..........HEWLETT-PACKARD ____ ___ / 351 East Evelyn Ave, Mt. View, CA. 94039 / / / / Tel T(415)-694-2542 Fax T(415)-694-2244 __/ __/ _____/ Internet................johnb@mtv.hp.com / HPDesk...............John Bria/HPATC3/00 ___________ __/ __________________________________________________________