[GROOVY-6360] GString performance is slow with String's method

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 2.1.7
• Fix Version/s: 3.0.8, 4.0.0-alpha-3
• Component/s: groovy-jdk
• Assignee: Paul King
• Reporter: Linh Pham
• Created: 24/Sep/13 08:59
• Updated: 05/Mar/24 01:39
• Resolved: 15/Feb/21 02:06

Description

GString implementation of String's method is very expensive. With trim(), it can be 10 times slower than String's counterpart.

Steps to reproduce:
A small test program showed GString.trim() is 10 times slower than String.trim().

def a = " content "
def b = " ${'content'} "
println "a class: ${a.class}"    //output: class java.lang.String
println "b class: ${b.class}"    //output: class org.codehaus.groovy.runtime.GStringImpl
long start = System.currentTimeMillis()
10000000.times {
    a.trim()
}
println "String trim completed in ${System.currentTimeMillis() - start} ms."  //output *909* ms

start = System.currentTimeMillis()
10000000.times {
    b.trim()
}
println "GString trim completed in ${System.currentTimeMillis() - start} ms."  //output: *9321 *ms

We can get around the problem by calling toString() on GString before invoking methods, BUT it should be supported inside the Groovy runtime.

More info at this thread: http://markmail.org/thread/4cti6dgb7pmrzqbl

Issue Links

• is related to: LOG4J2-3017 Groovy logging of GString with $ notation is very slow
• links to: GitHub Pull Request #1496