Questions about compress & ra_pages

Hi everybody, I'd like to do a couple of questions: 1.-What's the meaning of <compress> in onstat -p? 2.-I have the next ratio = rapgs_used/(btradata+btraidx+dpra)=99.7%. Would it be a good operation to increase the RA_PAGES and RA_THRESHOLD values(now 20/10)? I think that if a great number of pages are used, I'll improve i/o ratio increasing it. if that's right, when must i stop increasing? When it decreases up to 95%? Thanks in advance Pablo F Herrero Fernandez Gijon Asturias (Spain) Sent via Deja.com http://www.deja.com/ Before you buy.

Pablo Herrero wrote: > > Hi everybody, > I'd like to do a couple of questions: > 1.-What's the meaning of <compress> in onstat -p? The number of times two index pages were compressed back to one due to key deletions. > 2.-I have the next ratio = rapgs_used/(btradata+btraidx+dpra)=99.7%. Pretty good. > Would it be a good operation to increase the RA_PAGES and RA_THRESHOLD > values(now 20/10)? I think that if a great number of pages are used, > I'll improve i/o ratio increasing it. if that's right, when must i stop > increasing? When it decreases up to 95%? No try to keep the RA Usage Ration above 99%. I would say stop when either it drops below 99% or your read/write cache percentages begin to drop which will normally happen first. Also watch your Bufwaits Ratio this can drop a bit if the RA is too high. BTW if you have caching controllers with large (>=1MB) cache don't worry about RA so much since the controllers will be doing RA for you also. Art S. Kagel