Cache Everything Without Breaking the Bank

Posted by Matthew Hayward on

I’m often surprised at how small the buffer caches allocated to Oracle databases are. When I started as a DBA at Amazon in the early 2000’s, we were moving our Oracle databases to 32-bit Linux.  I shudder to recall all the crazy things we used to do, such as fiddling with the stack address space,…

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Lies, Damned Lies, and I/O Statistics

Posted by Matthew Hayward on

Given a description of gas dynamics and the atmosphere, you would be hard to pressed forecast tornadoes. The term emergence denotes the phenomena of surprising behaviors arising in complex systems.  Modern storage systems are complex, and full of emergent behavior that make forecasting application I/O performance fiendishly difficult. In collaboration with Kyle Hailey, Adam Leventhal,…

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Delphix – Defender of your SAN

Posted by Matthew Hayward on

One of the less obvious advantages of database virtualization is a reduction in the read I/O issued against the underlying physical storage (henceforth called “the SAN”) that ultimately stores the data for virtual databases. In practice, Delphix prevents around 60% of all non-production database I/O* from ever being issued to the SAN with the Delphix…

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