[jboss-dev] Interesting JBAS profiling results

[David M. Lloyd]

I was talking to Jason G on the phone, and he had an interesting idea: what 
happens when we profile the AS and look at the results by package rather 
than method?  This should give us a rough idea, by project, of where our 
startup time is being spent.  So I took a couple minutes and did just that, 
with some interesting results.

First, results for a minimal startup (results under 2% omitted):

9.7% - 2,418 ms - 41,306 hot spot inv. org.jboss.aop.pointcut
8.3% - 2,063 ms - 38,480 hot spot inv. org.jboss.reflect.plugins.introspection
5.9% - 1,461 ms - 373,799 hot spot inv. org.jboss.aop
5.7% - 1,415 ms - 52,528 hot spot inv. org.jboss.virtual.plugins.context.zip
5.7% - 1,411 ms - 294,922 hot spot inv. org.jboss.virtual.plugins.context
5.0% - 1,245 ms - 672,024 hot spot inv. org.jboss.aop.pointcut.ast
3.6% - 893 ms - 7,928 hot spot inv. org.jboss.classloader.spi.base
3.0% - 735 ms - 17,241 hot spot inv. org.jboss.dependency.plugins
2.9% - 720 ms - 20,215 hot spot inv. org.jboss.aop.util
2.8% - 697 ms - 150,242 hot spot inv. org.apache.log4j
2.6% - 636 ms - 272,879 hot spot inv. org.jboss.reflect.plugins
2.2% - 550 ms - 72,341 hot spot inv. org.jboss.metadata.plugins.context

As you can see, a minimal startup is dominated by AOP with VFS being a 
not-so-close second.

Next, a default startup, which shows somewhat different behavior:

10.5% - 25,156 ms - 5,827,279 hot spot inv. org.jboss.virtual.plugins.context
8.5% - 20,320 ms - 1,232,357 hot spot inv. 
org.jboss.virtual.plugins.context.zip
6.6% - 15,822 ms - 1,054,169 hot spot inv. 
org.jboss.virtual.plugins.vfs.helpers
6.4% - 15,319 ms - 297,465 hot spot inv. org.jboss.aop.pointcut
5.9% - 14,256 ms - 237,457 hot spot inv. org.jboss.dependency.plugins
5.1% - 12,148 ms - 6,769,258 hot spot inv. org.jboss.metadata.spi.scope
4.7% - 11,254 ms - 72,717 hot spot inv. javassist.bytecode
4.2% - 10,132 ms - 8,205,516 hot spot inv. org.jboss.dependency.spi
3.5% - 8,426 ms - 2,308,354 hot spot inv. org.jboss.aop
3.2% - 7,713 ms - 4,109,176 hot spot inv. org.jboss.aop.pointcut.ast
2.7% - 6,575 ms - 182,581 hot spot inv. org.jboss.reflect.plugins.introspection
2.7% - 6,366 ms - 52,818 hot spot inv. org.jboss.classloader.spi.base
2.2% - 5,284 ms - 333,613 hot spot inv. org.jboss.mx.server

VFS, AOP, metadata, classloading.  If I separate out filtered classes, it's 
basically the same story:

17.4% - 42,348 ms - 53,786,066 hot spot inv. java.lang
8.4% - 20,408 ms - 5,827,335 hot spot inv. org.jboss.virtual.plugins.context
8.2% - 19,943 ms - 21,005,518 hot spot inv. java.util
5.6% - 13,706 ms - 1,232,359 hot spot inv. 
org.jboss.virtual.plugins.context.zip
4.5% - 11,068 ms - 297,465 hot spot inv. org.jboss.aop.pointcut
3.5% - 8,531 ms - 72,717 hot spot inv. javassist.bytecode
3.4% - 8,266 ms - 6,769,258 hot spot inv. org.jboss.metadata.spi.scope
3.3% - 8,106 ms - 1,054,287 hot spot inv. org.jboss.virtual.plugins.vfs.helpers
3.2% - 7,754 ms - 237,461 hot spot inv. org.jboss.dependency.plugins
2.8% - 6,787 ms - 8,205,588 hot spot inv. org.jboss.dependency.spi
2.4% - 5,964 ms - 2,308,354 hot spot inv. org.jboss.aop
2.3% - 5,524 ms - 52,818 hot spot inv. org.jboss.classloader.spi.base
2.2% - 5,316 ms - 4,109,176 hot spot inv. org.jboss.aop.pointcut.ast

So it looks to me like we ought to be focusing our optimization efforts on 
VFS and AOP, maybe classloading as well.  I encourage folks to play around 
with profiling this way; it's fairly illuminating.

- DML