5) It scalability is a joke. I've worked as a Java contractor at a number of places and what a PERL/PHP/Python solution can get done in 5 boxes, it takes Java 30-40 boxes. This is NOT an exagerration. I think it's a side effect of some developers stuffing everything into the session and expecting clustering to fix everything.
Umm...I think you've been working in the wrong Java shops. I've never seen, nor do I believe it's possible, for a well-written python/perl/php app to be faster than a well-written Java app.
The startup of the JVM is horrendous. If you're doing even moderate web development, there is a minimum two to three second startup period for a web server. That simply doesn't exist in PERL/PHP/Python. There's no such thing as a permgen error in PERL/PHP/Python. I've never seen PERL/PHP/Python go off and spin the disk as furiously as Java trying to load classes. It's ridiculous.
Sure, Java's start-up is slow. But it shouldn't be an issue in web apps since your application will likely use threads if it's a Java app. I can see if your app was process-oriented, like many ruby/python web apps are, but with Java's native thread support it makes no sense to start up multiple processes unless you really have a need for the separation.
> Umm...I think you've been working in the wrong Java shops. I've never seen, nor do I believe it's possible, for a well-written python/perl/php app to be faster than a well-written Java app.
I've been in the industry over 20 years. I've seen plenty. It is easy to assume that the java and a JIT should be able to take advantage of all the extra information to make fast code. But in practice, when you add in all the frameworks and abstraction overhead, Java on the web is slower. I routinely hit stack traces well over 50 levels of depth. Benchmarks really don't take this into account.
>Sure, Java's start-up is slow. But it shouldn't be an issue in web apps since your application will likely use threads if it's a Java app. I can see if your app was process-oriented, like many ruby/python web apps are, but with Java's native thread support it makes no sense to start up multiple processes unless you really have a need for the separation.
I mostly agree with what you say. It is mostly a development issue. While most software development in Java attempts to be centered around TDD and therefore eliminate the whole start-restart cycle, the ugly truth is that there are reasons that tools like JRebel exist.
>I've been in the industry over 20 years. I've seen plenty. It is easy to assume that the java and a JIT should be able to take advantage of all the extra information to make fast code. But in practice, when you add in all the frameworks and abstraction overhead, Java on the web is slower. I routinely hit stack traces well over 50 levels of depth. Benchmarks really don't take this into account.
But your original post said Java was slow. It's not. Don't conflate the language with bad frameworks written with it.
Umm...I think you've been working in the wrong Java shops. I've never seen, nor do I believe it's possible, for a well-written python/perl/php app to be faster than a well-written Java app.
The startup of the JVM is horrendous. If you're doing even moderate web development, there is a minimum two to three second startup period for a web server. That simply doesn't exist in PERL/PHP/Python. There's no such thing as a permgen error in PERL/PHP/Python. I've never seen PERL/PHP/Python go off and spin the disk as furiously as Java trying to load classes. It's ridiculous.
Sure, Java's start-up is slow. But it shouldn't be an issue in web apps since your application will likely use threads if it's a Java app. I can see if your app was process-oriented, like many ruby/python web apps are, but with Java's native thread support it makes no sense to start up multiple processes unless you really have a need for the separation.