Kodo.util.DataStoreException: Backend start-up failed: FATAL

Question

when we do one test which concurrent users number is 800, there will cause
following exception:
kodo.util.DataStoreException: Backend start-up failed: FATAL: Sorry, too
many clients already
would you tell me what will cause the exception? and how to support more
concurrent users?

Answer 1

yes, this is my configure error.
when we reduce the MaxActive number(kodo db con pool size must smaller
then the allowed DB connections number), then the error not happen.
thanks a lot.
Marc Prud'hommeaux wrote:
Is your database configured to allow 200 simultaneous connections (as
you have specified in the "MaxActive=200" parameter of the
"kodo.ConnectionFactoryProperties" property)? If not, can you reduce
this number down to the maximum allowed by your database, and let us
know if the error still happens?
In article <[email protected]>, flamingo wrote:
kodo.properties as following:
# Database connection properties
javax.jdo.option.ConnectionDriverName=org.postgresql.Driver
javax.jdo.option.ConnectionUserName=xxx
javax.jdo.option.ConnectionPassword=xxx
javax.jdo.option.ConnectionURL=jdbc:postgresql://localhost/skillsdb
javax.jdo.option.Optimistic=true
javax.jdo.option.RetainValues=false
javax.jdo.option.RestoreValues=false
javax.jdo.option.NontransactionalRead=true
javax.jdo.option.NontransactionalWrite=false
javax.jdo.option.IgnoreCache=true
javax.jdo.PersistenceManagerFactoryClass=kodo.jdbc.runtime.JDBCPersistenceManagerFactory
>>
kodo.LicenseKey=xxx
kodo.ConnectionFactoryProperties=MaxCachedStatements=0, MaxActive=200,
MaxWait=5000, TestOnBorrow=true, ValidationSQL="SELECT GETDATE()"
kodo.ConnectionRetainMode=transaction
kodo.DataCache=true(CacheSize=10000)
kodo.QueryCache=true(CacheSize=5000)
#kodo.FlushBeforeQueries=true
kodo.RemoteCommitProvider=sjvm
kodo.ManagedRuntime=TransactionManagerName=java:/TransactionManager
kodo.PersistenceManagerImpl=EvictFromDataCache=true
kodo.jdbc.DBDictionary=postgres(StoreCharsAsNumbers=false)
kodo.jdbc.MappingFactory=metadata
kodo.jdbc.SchemaFactory: file(FileName=schema.xml)
kodo.jdbc.SequenceFactory=PrimaryKeyColumn=PKX, SequenceColumn=SEQUENCEX,
TableName=JDO_SEQUENCEX
and I check codes, we had closed all extent iterators, query results, PMs,
etc.
thanks a lot.
Abe White wrote:
There aren't any nested exceptions? That's the only trace you see?
In any case, the message is from your JDBC driver, which is probablyrelaying it
directly from your database. It is not a Kodo error message; Kodo is
only
wrapping the SQLException in a subclass of JDOException. As Patricksuggested,
the error probably means that your database can't handle the number ofclients
you're throwing at it. One possible reason for this is that you aren'tfreeing
up connections. Can you post your kodo.properties? Under default
settings
Kodo
doesn't hold onto database connections much, but under certain settings
it
becomes more important to remember to close your extent iterators, query
results, PMs, etc.
Marc Prud'hommeaux
SolarMetric Inc.