Scripting language performance

[测试部_贺寅]

Hello,
  In another thread, I noticed Philippe mentioned that " JSR223 Samplers + 
Groovy  + Caching" is a better choice then Beanshell. Since I used a lot of 
Beanshell in my scripts and never pay attention to it, I decided to make  an 
investigation of this issue. 
  I simplified one of my beanshell script, rewrited it into groovy and rhino 
and put them into script-samplers instead of  pre-processors. 
The result turned out that 
1) Beanshell is better than other solutions
2) Groovy and javascript will cause some gc problems.
3) Groovy
3) BSF and JSR223 seems that waste some cpu time on their framework.

Am I  doing something wrong? 

(Thread:10, Loop 500)
Label   Samples Average Median  90%     Min     Max     Error%  Throughput      
KB/sec  GC occurs
JSR223-groovy   5000    59      39      119     6       3077    0       
145.2137546     0       1~2
JSR223-rhino    5000    2       1       2       0       314     0       
851.9338899     0       frequently
BeanShell Sampler       5000    1       1       2       0       402     0       
1068.832835     0       0
BSF-beanshell   5000    33      27      63      3       328     0       
270.6506441     0       0
BSF-javascript  5000    20      6       44      1       640     0       
324.7174958     12.68427718     frequently

Environments: JMeter 2.8, 
Uncomment " jsr223.compiled_scripts_cache_size" in jmeter.properties
Groovy version: groovy-all-2.0.6
JVM_OPTS:
  set HEAP=-Xms512m -Xmx512m
  set NEW=-XX:NewSize=128m -XX:MaxNewSize=128m
  set SURVIVOR=-XX:SurvivorRatio=8 -XX:TargetSurvivorRatio=50%
  set TENURING=-XX:MaxTenuringThreshold=2
  set RMIGC=-Dsun.rmi.dgc.client.gcInterval=600000 
-Dsun.rmi.dgc.server.gcInterval=600000
  set PERM=-XX:PermSize=64m -XX:MaxPermSize=64m

Script for Beanshell and groovy:
for (int i=0;i<10;i++){
  line="1027448,1".split(",");
  pid=line[0];
  mid=line[1];
  vars.put("pid"+i,pid);
  vars.put("mid"+i,mid);
}
cartParam="";
for (int i=0;i<10;i++){
  pid=vars.get("pid"+i);
  mid=vars.get("mid"+i);
  param=mid+"_"+pid+"_"+"0_0_1=1";
  if (cartParam=="")
    cartParam=param;
  else
    cartParam+=","+param;
}
vars.put("cartParam",cartParam);

Script for rhino and javascript:
for (var i=0;i<10;i++){
  line="1027448,1".split(",");
  pid=line[0];
  mid=line[1];
  vars.put("pid"+i,pid);
  vars.put("mid"+i,mid);
}
var cartParam="";
for (var i=0;i<10;i++){
  pid=vars.get("pid"+i);
  mid=vars.get("mid"+i);
  param=mid+"_"+pid+"_"+"0_0_1=1";
  if (cartParam=="")
    cartParam=param;
  else
    cartParam+=","+param;
}
vars.put("cartParam",cartParam);