958963 wrote:what value would be acceptable to you & WHY that value?
I have installed SAP on Oracle 10G 10.2.0.4 patch level on RHEL5.3
i want to know How can i set the oracle memory parameter? any calculation behind it or other techninque.
server Memory around 32 GB
oracle installed on 16 GB + 16 GB for SAP instance.
Due to which Buffer Quality hit ration not more then 74%.
958963 wrote:The use of buffer cache is to store and provide the data from the memory. This would save eventually the disk reads to happen again and again after the necessary first time. But what you are doing wrong is to merge or correlate both buffer cache with its hit ratio. Ratio is what is it is, a ratio and any given time, it can be anything and is tweaked based on the operations that you perform in the db. This was a good factor when the memory was very costly and having everything in the memory was a good idea-obviously that the db's also were very small. Now, this is not a constraint anymore. So if you have a high ratio, that's not a proof that the entire db is performing very good. It may be a good factor to tell specifically about the buffer cache, which also won't be a correct statement to make as the ratio can be influenced . So use a more better approach like taking a Statspack report of both good and bad times and compare to find where are the deltas and the best, ask your users and check your service request queue. If there isn't anything popping in it up , you and your db are doing a good job.
so what should i do ?
if buffer quality is less; may be accure no issue of performance.?
OR suggest how can i check my DB is running good performance?