> In fact, JVM doesn't start slow. The fact is most Java web apps start slow. The more libraries a Java web app depends, the slower it starts. Depending on wha

> In fact, JVM doesn't start slow. The fact is most Java web apps start slow. The more libraries a Java web app depends, the slower it starts. Depending on what definition for "slow" you are using it absolutely starts slow. As mentioned in a cousin comment, the JVM takes ~100ms to get to user code. This makes it impractical for small applications where the user's code takes less than a second to complete. It certainly gets slower with more libraries, but for some applications ~100ms added to startup makes using Java not viable. Just some hard data to support Java being slow. I ran Hello Worlds in Java, C, Node, Python, and Ruby. Java is the slowest out of all the languages I tested. time java HelloWorld Hello, World real 0m0.170s user 0m0.148s sys 0m0.012s time helloWorld Hello, World! real 0m0.028s user 0m0.004s sys 0m0.008s time nodejs hello.js hello world real 0m0.136s user 0m0.104s sys 0m0.012s time python hello.py Hello World real 0m0.050s user 0m0.016s sys 0m0.020s time ruby hello.rb Hello World real 0m0.111s user 0m0.064s sys 0m0.028s