Hi Dimuthu, On Fri, Feb 26, 2010 at 9:38 AM, Dimuthu Gamage <[email protected]> wrote:
> Hi, > > I think What 'READ_COMMITED' do is, in a case of doing reading, it will > continue reading the commited data from the tables locked by others. So I > think what 'READ_COMMITED' guarantee is , if all the operation are 'READ' > then it will not dead lock. But Apparently we are doing some 'WRITE' > operations in that test case. so deadlocks are possible. > > I'm trying to list the sequence of database accesses for simple GET, PUT, > DELETE registry operations at here[1]. So we can identify which operation > can cause the deadlocks. > Since we support transactions spanning across multiple operations, this could be theoretically any N number of operations. What we should be doing here, is defining a protocol to handle situations causing a deadlock. This shouldn't result in a performance overhead if this is properly designed and well written. Also, the benefits are that we will not be loosing transactions, by means of a retrying logic. Thanks, Senaka. > > Thanks > Dimuthu > > [1] > https://spreadsheets.google.com/a/wso2.com/ccc?key=tX5iHIbwTIDDuyF8uwsERiw&hl=en > > > On Fri, Feb 26, 2010 at 9:14 AM, Amila Suriarachchi <[email protected]>wrote: > >> >> >> On Fri, Feb 26, 2010 at 8:21 AM, Dimuthu Gamage <[email protected]> wrote: >> >>> >>> >>> On Fri, Feb 26, 2010 at 7:50 AM, Amila Suriarachchi <[email protected]>wrote: >>> >>>> >>>> >>>> On Wed, Feb 24, 2010 at 12:03 PM, Sumedha Rubasinghe >>>> <[email protected]>wrote: >>>> >>>>> >>>>> On Wed, Feb 24, 2010 at 11:57 AM, Ruwan Linton <[email protected]> wrote: >>>>> >>>>>> Senaka Fernando wrote: >>>>>> > This could be due to overlapping transactions in this particular >>>>>> > component that attempts to write to the registry at once. >>>>>> So does this mean that Registry cannot handle concurrent connections >>>>>> to >>>>>> a particular registry resource/collection? Well, even in that case it >>>>>> shouldn't deadlock :-( >>>>>> >>>>> >>>>> If an insert (write) happens the database locks the table allowing only >>>>> read. So the only option available for us is to speed up write operation. >>>>> working on it.. >>>>> >>>> >>>> hi Sumedha, >>>> >>>> What is the transaction isolation level you use for these transactions? >>>> >>> >>> It is read committed. >>> >> Do you know why this deadlocks occur?. At this isolation level >> transactions do not have to lock the tables isn't it? >> >> Amila. >> >> >>> Thanks >>> Dimuthu >>> >>>> >>>> Amila. >>>> >>>>> >>>>> /sumedha >>>>> >>>>> >>>>>> Thanks, >>>>>> Ruwan >>>>>> > >>>>>> > Thanks, >>>>>> > Senaka. >>>>>> > >>>>>> > On Wed, Feb 24, 2010 at 11:28 AM, Hiranya Jayathilaka >>>>>> > <[email protected] <mailto:[email protected]>> wrote: >>>>>> > >>>>>> > Following exception encountered in the ESB while updating a >>>>>> proxy >>>>>> > service: >>>>>> > >>>>>> > >>>>>> > Exception in thread "Thread-23" >>>>>> > >>>>>> org.wso2.carbon.mediation.initializer.persistence.ServiceBusPersistenceException: >>>>>> > Error while saving mediation configuration changes >>>>>> > at >>>>>> > >>>>>> org.wso2.carbon.mediation.initializer.persistence.MediationPersistenceManager.handleException(MediationPersistenceManager.java:278) >>>>>> > at >>>>>> > >>>>>> org.wso2.carbon.mediation.initializer.persistence.MediationPersistenceManager.access$1200(MediationPersistenceManager.java:48) >>>>>> > at >>>>>> > >>>>>> org.wso2.carbon.mediation.initializer.persistence.MediationPersistenceManager$MediationPersistenceWorker.run(MediationPersistenceManager.java:320) >>>>>> > Caused by: >>>>>> > >>>>>> org.wso2.carbon.mediation.initializer.persistence.ServiceBusPersistenceException: >>>>>> > Unable to persist the proxy service in the path : >>>>>> > /repository/synapse/proxy-services/FooProxy >>>>>> > at >>>>>> > >>>>>> org.wso2.carbon.mediation.initializer.persistence.registry.AbstractRegistryStore.handleException(AbstractRegistryStore.java:101) >>>>>> > at >>>>>> > >>>>>> org.wso2.carbon.mediation.initializer.persistence.registry.ProxyServiceRegistryStore.persistElement(ProxyServiceRegistryStore.java:72) >>>>>> > at >>>>>> > >>>>>> org.wso2.carbon.mediation.initializer.persistence.AbstractStore.saveToRegistry(AbstractStore.java:154) >>>>>> > at >>>>>> > >>>>>> org.wso2.carbon.mediation.initializer.persistence.AbstractStore.save(AbstractStore.java:82) >>>>>> > at >>>>>> > >>>>>> org.wso2.carbon.mediation.initializer.persistence.MediationPersistenceManager.persistElement(MediationPersistenceManager.java:335) >>>>>> > at >>>>>> > >>>>>> org.wso2.carbon.mediation.initializer.persistence.MediationPersistenceManager.access$1000(MediationPersistenceManager.java:48) >>>>>> > at >>>>>> > >>>>>> org.wso2.carbon.mediation.initializer.persistence.MediationPersistenceManager$MediationPersistenceWorker.run(MediationPersistenceManager.java:314) >>>>>> > Caused by: >>>>>> > org.wso2.carbon.registry.core.exceptions.RegistryException: >>>>>> Unable >>>>>> > to persist element >>>>>> > at >>>>>> > >>>>>> org.wso2.carbon.mediation.initializer.persistence.registry.AbstractRegistryStore.persistElement(AbstractRegistryStore.java:95) >>>>>> > at >>>>>> > >>>>>> org.wso2.carbon.mediation.initializer.persistence.registry.ProxyServiceRegistryStore.persistElement(ProxyServiceRegistryStore.java:69) >>>>>> > ... 5 more >>>>>> > Caused by: >>>>>> > org.wso2.carbon.registry.core.exceptions.RegistryException: >>>>>> Failed >>>>>> > to add log entry for resource >>>>>> > /_system/config/repository/synapse/proxy-services. Deadlock >>>>>> > detected. The current transaction was rolled back. Details: >>>>>> > Session #9 (user: WSO2CARBON) is waiting to lock >>>>>> > PUBLIC.REG_RESOURCE while locking PUBLIC.REG_ASSOCIATION >>>>>> > (exclusive), PUBLIC.REG_LOG (exclusive). >>>>>> > Session #12 (user: WSO2CARBON) is waiting to lock PUBLIC.REG_LOG >>>>>> > while locking PUBLIC.REG_CONTENT_HISTORY (exclusive), >>>>>> > PUBLIC.REG_RESOURCE_HISTORY (exclusive), PUBLIC.REG_RESOURCE >>>>>> > (exclusive), PUBLIC.REG_CONTENT (exclusive), PUBLIC.REG_SNAPSHOT >>>>>> > (exclusive).; SQL statement: >>>>>> > INSERT INTO REG_LOG (REG_PATH, REG_USER_ID, REG_LOGGED_TIME, >>>>>> > REG_ACTION, REG_ACTION_DATA, REG_TENANT_ID) VALUES (?, ?, ?, ?, >>>>>> ?, >>>>>> > ?) [40001-112] >>>>>> > at >>>>>> > >>>>>> org.wso2.carbon.registry.core.jdbc.dao.LogsDAO.addLog(LogsDAO.java:79) >>>>>> > at >>>>>> > >>>>>> org.wso2.carbon.registry.core.jdbc.Repository.update(Repository.java:966) >>>>>> > at >>>>>> > >>>>>> org.wso2.carbon.registry.core.jdbc.Repository.updateParent(Repository.java:947) >>>>>> > at >>>>>> > >>>>>> org.wso2.carbon.registry.core.jdbc.Repository.delete(Repository.java:403) >>>>>> > at >>>>>> > >>>>>> org.wso2.carbon.registry.core.jdbc.EmbeddedRegistry.delete(EmbeddedRegistry.java:807) >>>>>> > at >>>>>> > >>>>>> org.wso2.carbon.registry.core.session.UserRegistry.delete(UserRegistry.java:625) >>>>>> > at >>>>>> > >>>>>> org.wso2.carbon.mediation.initializer.persistence.registry.AbstractRegistryStore.persistElement(AbstractRegistryStore.java:79) >>>>>> > ... 6 more >>>>>> > Caused by: org.h2.jdbc.JdbcSQLException: Deadlock detected. The >>>>>> > current transaction was rolled back. Details: >>>>>> > Session #9 (user: WSO2CARBON) is waiting to lock >>>>>> > PUBLIC.REG_RESOURCE while locking PUBLIC.REG_ASSOCIATION >>>>>> > (exclusive), PUBLIC.REG_LOG (exclusive). >>>>>> > Session #12 (user: WSO2CARBON) is waiting to lock PUBLIC.REG_LOG >>>>>> > while locking PUBLIC.REG_CONTENT_HISTORY (exclusive), >>>>>> > PUBLIC.REG_RESOURCE_HISTORY (exclusive), PUBLIC.REG_RESOURCE >>>>>> > (exclusive), PUBLIC.REG_CONTENT (exclusive), PUBLIC.REG_SNAPSHOT >>>>>> > (exclusive).; SQL statement: >>>>>> > INSERT INTO REG_LOG (REG_PATH, REG_USER_ID, REG_LOGGED_TIME, >>>>>> > REG_ACTION, REG_ACTION_DATA, REG_TENANT_ID) VALUES (?, ?, ?, ?, >>>>>> ?, >>>>>> > ?) [40001-112] >>>>>> > at org.h2.message.Message.getSQLException(Message.java:107) >>>>>> > at org.h2.message.Message.getSQLException(Message.java:118) >>>>>> > at org.h2.message.Message.getSQLException(Message.java:77) >>>>>> > at org.h2.table.TableData.doLock(TableData.java:428) >>>>>> > at org.h2.table.TableData.lock(TableData.java:375) >>>>>> > at org.h2.command.dml.Insert.update(Insert.java:99) >>>>>> > at >>>>>> org.h2.command.CommandContainer.update(CommandContainer.java:71) >>>>>> > at org.h2.command.Command.executeUpdate(Command.java:207) >>>>>> > at >>>>>> > >>>>>> org.h2.jdbc.JdbcPreparedStatement.executeUpdateInternal(JdbcPreparedStatement.java:139) >>>>>> > at >>>>>> > >>>>>> org.h2.jdbc.JdbcPreparedStatement.executeUpdate(JdbcPreparedStatement.java:128) >>>>>> > at >>>>>> > >>>>>> org.apache.commons.dbcp.DelegatingPreparedStatement.executeUpdate(DelegatingPreparedStatement.java:102) >>>>>> > at >>>>>> > >>>>>> org.wso2.carbon.registry.core.jdbc.dao.LogsDAO.addLog(LogsDAO.java:72) >>>>>> > ... 12 more >>>>>> > >>>>>> > Thanks >>>>>> > -- >>>>>> > Hiranya Jayathilaka >>>>>> > Software Engineer; >>>>>> > WSO2 Inc.; http://wso2.org >>>>>> > E-mail: [email protected] <mailto:[email protected]>; Mobile: >>>>>> +94 >>>>>> > 77 633 3491 >>>>>> > Blog: http://techfeast-hiranya.blogspot.com >>>>>> > >>>>>> > _______________________________________________ >>>>>> > Carbon-dev mailing list >>>>>> > [email protected] <mailto:[email protected]> >>>>>> > https://mail.wso2.org/cgi-bin/mailman/listinfo/carbon-dev >>>>>> > >>>>>> > >>>>>> > >>>>>> > >>>>>> > -- >>>>>> > Senaka Fernando >>>>>> > Software Engineer >>>>>> > WSO2 Inc. >>>>>> > E-mail: senaka AT wso2.com <http://wso2.com>; Mobile: +94 77 322 >>>>>> 1818 >>>>>> > >>>>>> > http://www.wso2.com/ - "Lean . Enterprise . Middleware" >>>>>> > >>>>>> ------------------------------------------------------------------------ >>>>>> > >>>>>> > _______________________________________________ >>>>>> > Carbon-dev mailing list >>>>>> > [email protected] >>>>>> > https://mail.wso2.org/cgi-bin/mailman/listinfo/carbon-dev >>>>>> > >>>>>> >>>>>> >>>>>> -- >>>>>> Ruwan Linton >>>>>> Technical Lead & Product Manager; WSO2 ESB; http://wso2.org/esb >>>>>> WSO2 Inc.; http://wso2.org >>>>>> email: [email protected]; cell: +94 77 341 3097 >>>>>> blog: http://blog.ruwan.org >>>>>> >>>>>> Lean . Enterprise . Middleware >>>>>> >>>>>> >>>>>> _______________________________________________ >>>>>> Carbon-dev mailing list >>>>>> [email protected] >>>>>> https://mail.wso2.org/cgi-bin/mailman/listinfo/carbon-dev >>>>>> >>>>> >>>>> >>>>> _______________________________________________ >>>>> Carbon-dev mailing list >>>>> [email protected] >>>>> https://mail.wso2.org/cgi-bin/mailman/listinfo/carbon-dev >>>>> >>>>> >>>> >>>> _______________________________________________ >>>> Carbon-dev mailing list >>>> [email protected] >>>> https://mail.wso2.org/cgi-bin/mailman/listinfo/carbon-dev >>>> >>>> >>> >>> _______________________________________________ >>> Carbon-dev mailing list >>> [email protected] >>> https://mail.wso2.org/cgi-bin/mailman/listinfo/carbon-dev >>> >>> >> >> _______________________________________________ >> Carbon-dev mailing list >> [email protected] >> https://mail.wso2.org/cgi-bin/mailman/listinfo/carbon-dev >> >> > > _______________________________________________ > Carbon-dev mailing list > [email protected] > https://mail.wso2.org/cgi-bin/mailman/listinfo/carbon-dev > > -- Senaka Fernando Software Engineer WSO2 Inc. E-mail: senaka AT wso2.com; Mobile: +94 77 322 1818 http://www.wso2.com/ - "Lean . Enterprise . Middleware"
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