Simon Willison’s Weblog

The latest SQLite 3.8.7 alpha version is 50% faster than the 3.7.17 release from 16 months ago.  That is to say, it does 50% more work using the same number of CPU cycles. [...] The 50% faster number above is not about better query plans.  This is 50% faster at the low-level grunt work of moving bits on and off disk and search b-trees.  We have achieved this by incorporating hundreds of micro-optimizations.  Each micro-optimization might improve the performance by as little as 0.05%.  If we get one that improves performance by 0.25%, that is considered a huge win.  Each of these optimizations is unmeasurable on a real-world system (we have to use cachegrind to get repeatable run-times) but if you do enough of them, they add up.

— D. Richard Hipp