In our last blog post “Sizing post #4: How much pain are we willing to tolerate?” we talked about how much pain we can tolerate so we can decide on which percentile we want to size our database workload. It is not a size fits all because it depends on the database workload profile, some… Continue reading Sizing post #5: How to map our existing processing power to new hardware.
We have gone through 3 posts already and have learned how to standardize ASH data for sizing, reviewed some basic statistics like mean, median, maximum and minimum and the use of percentiles to calculate the CPU requirement for a single instance database. In this post we want to show a way to figure out what… Continue reading Sizing post #4: How much pain are we willing to tolerate?
Hello, here we are now on post #3 on my favorite topic: “sizing”. So far, we have learned how to standardize data coming from ASH to use it for sizing. Sizing post #1: How to standardize ASH data for sizing. In our previous post we talked about average (mean), median, minimum, and maximum. Sizing post… Continue reading Sizing post #3: Understanding percentiles
This is the second blog entry for a series of posts related to the topic of “sizing.” This time we are going to chart the cpu usage and calculate the average (mean), median, minimum, and maximum from the ASH data we standardized in previous post “Sizing post #1: How to standardize ASH data for sizing.”… Continue reading Sizing post #2: The not so good mean, the bad median, and the ugly minimum and maximum
This is a first blog entry for a series of posts related to the topic of “sizing.” The standardization of ASH data for sizing consists of aggregating the number of sessions on CPU, adding the 0’s (zeroes) to this aggregated data and filling in with sample times to have 10 seconds equidistant sample times. The… Continue reading Sizing post #1: How to standardize ASH data for sizing
Today we are featuring the FILE_DATASTORE which is used to index files that reside in the operating file system. There is no need to upload the documents into the database. File names are stored in a varchar column, one document per row. We are demonstrating this with a set of recipes in PDF format and… Continue reading How to Index Files Residing in the OS File System
This post is to show how a frequency histogram helps the optimizer to come up with a more optimal execution plan. I will show how the optimizer chooses a sub-optimal plan assuming uniform distribution of data where the data is skewed, then show how a frequency histogram helps improving the optimizer decisions. I am creating… Continue reading How a Frequency Histogram Works