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Blogging live again!

I am returning to Google's blogger after a long hiatus. Initially, I plan to discuss a new project I have been working on -- a collection agent to gather data from several key SQL Server Dynamic Management views (DMVs) and transform that data into Windows performance counters. In a series of blog posts, I will try and make the case that generating Windows performance counters from several of these DMVs is a useful thing to do. I believe the project has the potential to help DBAs address issues in physical database design that play a pivotal role in application performance, issues that are too often ignored or, unfortunately, treated in a less than rigorous manner. I am looking to engage with other database performance professionals who have experience in this area.

Over the past several years, I have not been posting here, but instead to a WordPress web site named that I own. There is a lot to like about WordPress, including superior composition tools. Unfortunately, Google's web crawler seldom gets around to that web site, so I don't see enough Readers there. As I am writing this series of posts on SQL Server performance, I will also pull some of the older material I have published on the other site.


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High Resolution Clocks and Timers for Performance Measurement in Windows.

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Ballooning is a complicated topic, so bear with me if this post is much longer than the previous ones in this series.

As described earlier, VMware installs a balloon driver inside the guest OS and signals the driver to begin to “inflate” when it begins to encounter contention for machine memory, defined as the amount of free machine memory available for new guest machine allocation requests dropping below 6%. In the benchmark example I am discussing here, the Memory Usage counter rose to 98% allocation levels and remained there for duration of the test while all four virtual guest machines were active.

Figure 7, which shows the guest machine Memory Granted counter for each guest, with an overlay showing the value of the Memory State counter reported at the end of each one-minute measurement interval, should help to clarify the state of VMware memory-managemen…