Hi Hiko,
I am using this settings for IBM JRE:
MOM:
8GB RHEL 5.5 VMWare:
lax.nl.java.option.additional=-Dorg.owasp.esapi.resources=./config/esapi -Djava.awt.headless=true -Xgcpolicy:gencon -Xcompressedrefs -verbose:sizes -Xmns3G -Xmnx3G -Xms5G -Xmx5G -verbosegc -Xverbosegclog:logs/garbagecollection.log -Xss512k -Dmail.mime.charset=UTF-8
EMs:
16GB RHEL 5.5 VMWare (I am currently investigating whether it is better to configure nursery/tenured with 8GB/4GB or to leave the sizing to the JVM):
lax.nl.java.option.additional=-Xms12G -Xmx12G -Djava.awt.headless=true -Xgcpolicy:gencon -Xss512k -verbose:sizes -Xcompressedrefs -verbosegc -Xverbosegclog:logs/garbagecollection.log -Dmail.mime.charset=UTF-8
lax.nl.java.option.additional=-Xms12G -Xmx12G -Djava.awt.headless=true -Xgcpolicy:gencon -Xmns8G -Xmnx8G -Xmos4G -Xmox4G -Xss512k -verbose:sizes -Xcompressedrefs -verbosegc -Xverbosegclog:logs/garbagecollection.log -Dmail.mime.charset=UTF-8
8GB RHEL 5.5 VMWare (I am currently investigating whether it is better to configure nursery/tenured with 2GB/3GB or to leave the sizing to the JVM):
lax.nl.java.option.additional=-Xms5G -Xmx5G -Djava.awt.headless=true -Xgcpolicy:gencon -Xss512k -verbose:sizes -Xcompressedrefs -verbosegc -Xverbosegclog:logs/garbagecollection.log -Dmail.mime.charset=UTF-8
lax.nl.java.option.additional=-Xms5G -Xmx5G -Djava.awt.headless=true -Xgcpolicy:gencon -Xmns2G -Xmnx2G -Xmos3G -Xmox3G -Xss512k -verbose:sizes -Xcompressedrefs -verbosegc -Xverbosegclog:logs/garbagecollection.log -Dmail.mime.charset=UTF-8
My experiences with different settings:
- Depending on the live metric count and the connected agents, the size of the nursery area has to be really big that the EM can harvest all the metrics and persist them into the smartstor
- GenCon is the right gc policy because the scavenger tilt ratio is round about 90%. So there are only 10% objects in the survivor space in the nursery area and so the nursery gc cycles are very fast
- CPU is not the limiting ressource but the RAM and the heap size (for MOM and EMs)