BUFFERS

The sysadmin book says that the max number of BUFFERS for IDS is 512000. However, I just discovered that our number was set higher than that, and everything's working fine. In fact, we have read/write cache ratio's of around 95% (onstat -p). I was just wondering if anyone knew the detriments of having their # of BUFFERS higher than 512K. Also, anyone know the max # LRUs IDS can have? Thanks. -- Phillip "I always wanted to be the last guy on Earth, just to see if all those women were lying to me."

The maximum value of LRUS is 128 as for CLEANERS also. There is a bug in all versions upto and including 7.24UC7 that reports a spurious error message at startup time if you use 128 LRUs, complaining that your logical and physical logs sizes are zero (0) so I just use 127. I have not check to see if they fixed this one in 7.3x but it is harmless, only annoying. Art S. Kagel Phillip Tien wrote: > > The sysadmin book says that the max number of BUFFERS for IDS is > 512000. However, I just discovered that our number was set higher than > that, and everything's working fine. In fact, we have read/write cache > ratio's of around 95% (onstat -p). I was just wondering if anyone knew > the detriments of having their # of BUFFERS higher than 512K. Also, > anyone know the max # LRUs IDS can have? Thanks. > > -- > Phillip > > "I always wanted to be the last guy on Earth, just to see if all those > women were lying to me."

When you change a parameter in the ONCONFIG file and recycle your instance, the server will tell you what parameters were changed and their old and new values. If you have a value listed in your ONCONFIG file greater than the maximum, it will list the maximum instead of the value you listed in the file. You can, of course, test this by changing the parameter to 510,000 and recycling, then changing it to a value greater than 512,000. LRUS maximum, listed in the manual, is 128. HOWEVER, for an OLTP system, the normal setting for this parameter is NUMCPUVPS * 4 (with CLEANERS set to the same value). In DSS (Decision Support System) environments, it is BUFFERS / 1000 up to the maximum 128. Take care. =============================================== Clifton M. Bean cmbean@msn.com SAP/Informix Database Administrator Informix Certified Database Specialist Informix 4GL-Certified Informix D4GL-Certified Tekmetrics Certified Informix DBA Tekmetrics Certified RDBMS Developer =============================================== Phillip Tien <phillip.tien@wholefoods.com> wrote in message news:37BADD83.E813E299@wholefoods.com... > The sysadmin book says that the max number of BUFFERS for IDS is > 512000. However, I just discovered that our number was set higher than > that, and everything's working fine. In fact, we have read/write cache > ratio's of around 95% (onstat -p). I was just wondering if anyone knew > the detriments of having their # of BUFFERS higher than 512K. Also, > anyone know the max # LRUs IDS can have? Thanks. > > -- > Phillip > > "I always wanted to be the last guy on Earth, just to see if all those > women were lying to me." > >

Art: FYI it looks like this LRUS=128 is fixed in 7.31.UC2. allen "Art S. Kagel" wrote: > > The maximum value of LRUS is 128 as for CLEANERS also. There is a bug in > all versions upto and including 7.24UC7 that reports a spurious error > message at startup time if you use 128 LRUs, complaining that your logical and > physical logs sizes are zero (0) so I just use 127. I have not check > to see if they fixed this one in 7.3x but it is harmless, only annoying. > > Art S. Kagel > > Phillip Tien wrote: > > > > The sysadmin book says that the max number of BUFFERS for IDS is > > 512000. However, I just discovered that our number was set higher than > > that, and everything's working fine. In fact, we have read/write cache > > ratio's of around 95% (onstat -p). I was just wondering if anyone knew > > the detriments of having their # of BUFFERS higher than 512K. Also, > > anyone know the max # LRUs IDS can have? Thanks. > > > > -- > > Phillip > > > > "I always wanted to be the last guy on Earth, just to see if all those > > women were lying to me."