Archive for May, 2010

In an earlier article, we talked about actually initializing memory rather than just allocating it. This post will show how we can look at what is allocated in Linux, as well as when it shows as being in use and when it doesn’t. I found that memory will show up in pmap (really, pmap... »

Huge Pages is a feature available in later Linux kernels that provides two important benefits: 1. Locks the memory available to huge pages, so it cannot be paged to disk 2. Make the TLB (translation lookaside buffer) much smaller on the processor, as the number of entries is much smaller. This is due to... »

I had to analyze a performance problem this morning, and it occurred to me it is a good example of troubleshooting queries impacted by the clustering_factor of an index.  As such, below is the email exchange. I took a look, and I think I understand why the query optimizer is choosing a full scan... »