• Adam Thurgar

Are you scared to make changes?


Whilst contracting at an online share trading company, I noticed that 15 minutes before the market opened the senior DBA had a scheduled job to do an update statistics on a number of key tables and recompile a few highly used stored procedures. I asked why this was done and he said for performance when the market opened. After reviewing the performance I made some suggestions about other things we could try. Reduce parameter sniffing by having hard coded stored procedures for the top 20 stocks. Then before the market opens have a job that calls all of these stored procedures to prepopulate the data cache and have the most current plans in the plan cache, potentially clearing the plan cache before this was done. Changing the overnight updating of statistics to be more thorough by changing the scanning to a higher percentage or a full scan. All of these suggestions were ignored. What I observed during my time in this company was that the senior DBA got blamed for poor performance and outages. He had been intimidated by upper management, become gun shy and scared of making changes. How can you make things better if you don't make changes? Sure, not all of them may work, but doing nothing is not an option in my book.


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