[FREEMARKER-80] Performance bottleneck (from profiling)

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.3.26-incubating
• Component/s: engine
• Environment: Linux, Java 8
• Assignee: Unassigned
• Reporter: Shevek
• Created: 03/Oct/17 10:24
• Updated: 05/Apr/18 11:50
• Resolved: 05/Apr/18 11:50

Description

Major performance bottleneck running on a 32-core system, limits effective number of threads to about 6: PropertyDescriptor.getReadMethod() is synchronized, and blocks other threads. Partial stack follows:

java.beans.PropertyDescriptor.getReadMethod()
BeanModel.invokeThroughDescriptor()
BeanModel.get()
Dot._eval()

I suspect there's a workaround with using a method call directly in the FTL template, but I haven't figured it out yet. However, this is killing our performance. With Velocity, at the cost of a slower renderer, we can run all 32 cores, and get the job done faster.

I'm not entirely sure how to figure out which piece of FTL is causing this stack.