Hi experts,
Our J2EE server of Portal often restart automaticly recently when we edit content of Portal.
Syslog in MMC display as follow :
SAP Basis System: Operating system call recv failed (error no. 10054)
Default trace file information as follow :
#
#1.5#00145E166337005B0000001C0000175000042DA6D35ADC97#1176094440812#com.sap.portal
.portal#sap.com/irj#com.sap.portal.portal#netcare06cn#817####50c4c3d0e65611db899b0
0145e166337#SAPEngine_Application_Thread[impl:3]
8##0#0#Error#1#/System/Server#Java###Exception ID:12:5409/04/07_0044_118674050
[EXCEPTION]
#1#com.sapportals.portal.prt.component.PortalComponentException: Error in service call of Portal Component User : netcare06cn at com.sapportals.portal.prt.core.PortalRequestManager.handlePortalComponentException (PortalRequestManager.java:969) at com.sapportals.portal.prt.core.PortalRequestManager.callPortalComponent (PortalRequestManager.java:343) at com.sapportals.portal.prt.core.PortalRequestManager.dispatchRequest (PortalRequestManager.java:136) at com.sapportals.portal.prt.core.PortalRequestManager.dispatchRequest (PortalRequestManager.java:189) at com.sapportals.portal.prt.core.PortalRequestManager.runRequestCycle (PortalRequestManager.java:753) at com.sapportals.portal.prt.connection.ServletConnection.handleRequest (ServletConnection.java:240) at com.sapportals.portal.prt.dispatcher.Dispatcher$doService.run (Dispatcher.java:545) at java.security.AccessController.doPrivileged(Native Method) at com.sapportals.portal.prt.dispatcher.Dispatcher.service (Dispatcher.java:405) at javax.servlet.http.HttpServlet.service(HttpServlet.java:853) at com.sap.engine.services.servlets_jsp.server.servlet.InvokerServlet.service (InvokerServlet.java:156) at javax.servlet.http.HttpServlet.service(HttpServlet.java:853) at com.sap.engine.services.servlets_jsp.server.HttpHandlerImpl.runServlet (HttpHandlerImpl.java:390) at com.sap.engine.services.servlets_jsp.server.HttpHandlerImpl.handleRequest (HttpHandlerImpl.java:264) at com.sap.engine.services.httpserver.server.RequestAnalizer.startServlet (RequestAnalizer.java:347) at com.sap.engine.services.httpserver.server.RequestAnalizer.startServlet (RequestAnalizer.java:325) at com.sap.engine.services.httpserver.server.RequestAnalizer.invokeWebContainer (RequestAnalizer.java:887) at com.sap.engine.services.httpserver.server.RequestAnalizer.handle (RequestAnalizer.java:241) at com.sap.engine.services.httpserver.server.Client.handle(Client.java:92) at com.sap.engine.services.httpserver.server.Processor.request (Processor.java:148) at com.sap.engine.core.service630.context.cluster.session.ApplicationSessionMessageLi stener.process(ApplicationSessionMessageListener.java:33) at com.sap.engine.core.cluster.impl6.session.MessageRunner.run (MessageRunner.java:41) at com.sap.engine.core.thread.impl3.ActionObject.run(ActionObject.java:37) at java.security.AccessController.doPrivileged(Native Method) at com.sap.engine.core.thread.impl3.SingleThread.execute (SingleThread.java:100) at com.sap.engine.core.thread.impl3.SingleThread.run (SingleThread.java:170) Caused by: java.lang.OutOfMemoryError # #1.5#00145E166337005B0000001E0000175000042DA6D35AE2D4#1176094440812#com.sap.portal .portal#sap.com/irj#com.sap.portal.portal#netcare06cn#817####50c4c3d0e65611db899b0 0145e166337#SAPEngine_Application_Thread[impl:3] 8##0#0#Error#1#/System/Server#Java###Exception ID:12:5409/04/07_0045_118674050 [EXCEPTION] #1#com.sapportals.portal.prt.runtime.PortalRuntimeException:
PortalRuntimeException
at
com.sapportals.portal.prt.core.PortalRequestManager.handleRequestException
(PortalRequestManager.java:921)
at com.sapportals.portal.prt.core.PortalRequestManager.runRequestCycle
(PortalRequestManager.java:803)
at com.sapportals.portal.prt.connection.ServletConnection.handleRequest
(ServletConnection.java:240)
at com.sapportals.portal.prt.dispatcher.Dispatcher$doService.run
(Dispatcher.java:545)
at java.security.AccessController.doPrivileged(Native Method)
at com.sapportals.portal.prt.dispatcher.Dispatcher.service
(Dispatcher.java:405)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at
com.sap.engine.services.servlets_jsp.server.servlet.InvokerServlet.service
(InvokerServlet.java:156)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at com.sap.engine.services.servlets_jsp.server.HttpHandlerImpl.runServlet
(HttpHandlerImpl.java:390)
at
com.sap.engine.services.servlets_jsp.server.HttpHandlerImpl.handleRequest
(HttpHandlerImpl.java:264)
at com.sap.engine.services.httpserver.server.RequestAnalizer.startServlet
(RequestAnalizer.java:347)
at com.sap.engine.services.httpserver.server.RequestAnalizer.startServlet
(RequestAnalizer.java:325)
at
com.sap.engine.services.httpserver.server.RequestAnalizer.invokeWebContainer
(RequestAnalizer.java:887)
at com.sap.engine.services.httpserver.server.RequestAnalizer.handle
(RequestAnalizer.java:241)
at com.sap.engine.services.httpserver.server.Client.handle(Client.java:92)
at com.sap.engine.services.httpserver.server.Processor.request
(Processor.java:148)
at
com.sap.engine.core.service630.context.cluster.session.ApplicationSessionMessageLi
stener.process(ApplicationSessionMessageListener.java:33)
at com.sap.engine.core.cluster.impl6.session.MessageRunner.run
(MessageRunner.java:41)
at com.sap.engine.core.thread.impl3.ActionObject.run(ActionObject.java:37)
at java.security.AccessController.doPrivileged(Native Method)
at com.sap.engine.core.thread.impl3.SingleThread.execute
(SingleThread.java:100)
at com.sap.engine.core.thread.impl3.SingleThread.run
(SingleThread.java:170)
Caused by: java.lang.OutOfMemoryError
#
#1.5#00145E166337005D000000130000175000042DA6D4EFCAC7#1176094467359#System.err#sap
.com/irj#System.err#Guest#2####64ff4af0e65611dbbaa000145e166337#SAPEngine_Applicat
ion_Thread[impl:3]
_9##0#0#Error##Plain###com.sapportals.portal.prt.runtime.PortalRuntimeException:
Exception in connection#
#1.5#00145E166337005D000000140000175000042DA6D5275C51#1176094471000#com.sap.engine
.frame.Environment##com.sap.engine.frame.Environment#Guest#2####672add80e65611dbb4
f100145e166337#SAPEngine_Application_Thread[impl:3]
_9##0#0#Error#1#/System#Plain###FATAL: Caught OutOfMemoryError! Node will exit
with exit code 666#
#1.5#00145E166337005D000000150000175000042DA6D5275D14#1176094471000#com.sap.engine
.frame.Environment##com.sap.engine.frame.Environment#Guest#2####672add80e65611dbb4
f100145e166337#SAPEngine_Application_Thread[impl:3]
_9##0#0#Fatal#1#/System#Java###FATAL: Caught OutOfMemoryError! Node will exit with
exit code 666
[EXCEPTION]
#1#java.lang.OutOfMemoryError
#
#1.5#00145E1663370019000000000000176000042DA6D60249A1#1176094485140#tcmobileadminc
oresetup##tcmobileadmincoresetup#######SAPEngine_System_Thread[impl:5]
_39##0#0#Error##Plain###SetupConfigurationService().after<super()>#
#1.5#00145E1663370019000000010000176000042DA6D6024EAE#1176094485140#tcmobileadminc
oresetup##tcmobileadmincoresetup#######SAPEngine_System_Thread[impl:5]
_39##0#0#Error##Plain###SetupConfigurationService
().after<applicationServiceContext = ctx;>#
#1.5#00145E1663370019000000020000176000042DA6D6025DE6#1176094485140#tcmobileadminc
oresetup##tcmobileadmincoresetup#######SAPEngine_System_Thread[impl:5]
39##0#0#Error##Plain###mobilesetupGenerationdoes exist.#
#1.5#00145E1663370019000000030000176000042DA6D602AF43#1176094485156#tcmobileadminc
oresetup##tcmobileadmincoresetup#######SAPEngine_System_Thread[impl:5]
_39##0#0#Error##Plain###SetupApplicationServiceFrame.after<7>#
#1.5#00145E1663370019000000040000176000042DA6D602B302#1176094485156#tcmobileadminc
oresetup##tcmobileadmincoresetup#######SAPEngine_System_Thread[impl:5]
_39##0#0#Error##Plain###SetupApplicationServiceFrame.after<8>#
#1.5#00145E166337002E000000000000176000042DA6D632E97C#1176094488328#com.sap.tc.lm.
ctc.confs.service.ServiceFrame##com.sap.tc.lm.ctc.confs.service.ServiceFrame######
#SAPEngine_System_Thread[impl:5]
_74##0#0#Info#1#/System/Server/CTC#Plain###Starting Configuration util service...#
#1.5#00145E166337002F000000000000176000042DA6D632F013#1176094488328#com.sap.tc.lm.
ctc.cul.j2eeengine.CULServiceFrame##com.sap.tc.lm.ctc.cul.j2eeengine.CULServiceFra
me#######SAPEngine_System_Thread[impl:5]_22##0#0#Info##Plain###entering
CulServiceFrame.start#
#1.5#00145E166337002F000000010000176000042DA6D63379C4#1176094488359#com.sap.tc.lm.
ctc.cul.j2eeengine.CULServiceFrame##com.sap.tc.lm.ctc.cul.j2eeengine.CULServiceFra
me#######SAPEngine_System_Thread[impl:5]_22##0#0#Info##Plain###deploymentListener
registered#
#1.5#00145E166337002E000000020000176000042DA6D6392D28#1176094488734#com.sap.tc.lm.
ctc.confs.service.ServiceFrame##com.sap.tc.lm.ctc.confs.service.ServiceFrame######
#SAPEngine_System_Thread[impl:5]
_74##0#0#Info#1#/System/Server/CTC#Plain###Configuration util service started
successfully.#
#1.5#00145E166337002F000000020000176000042DA6D63A4316#1176094488812#com.sap.tc.lm.
ctc.cul.j2eeengine.CULServiceFrame##com.sap.tc.lm.ctc.cul.j2eeengine.CULServiceFra
me#######SAPEngine_System_Thread[impl:5]_22##0#0#Info##Plain###Enum =
com.sap.engine.frame.core.load.res.CompoundEnumeration@13d12d43#
#1.5#00145E166337002F000000030000176000042DA6D63A654E#1176094488812#com.sap.tc.lm.
ctc.cul.j2eeengine.CULServiceFrame##com.sap.tc.lm.ctc.cul.j2eeengine.CULServiceFra
me#######SAPEngine_System_Thread[impl:5]_22##0#0#Info##Plain###Inputstream CTC
start file java.io.ByteArrayInputStream@2be3d80c#
#1.5#00145E166337002F000000040000176000042DA6D63C5450#1176094488937#com.sap.tc.lm.
ctc.cul.j2eeengine.CULServiceFrame##com.sap.tc.lm.ctc.cul.j2eeengine.CULServiceFra
me#######SAPEngine_System_Thread[impl:5]_22##0#0#Info##Plain###Object =
com.sap.tc.lm.ctc.cul.j2eeengine.CULStartup@2f3cf887#
#1.5#00145E166337002F000000050000176000042DA6D64010BC#1176094489187#com.sap.tc.lm.
ctc.cul.j2eeengine.CULStartup##com.sap.tc.lm.ctc.cul.j2eeengine.CULStartup#######S
APEngine_System_Thread[impl:5]
_22##0#0#Info#1#/System/Server/CTC#Plain###...ConfigManagerProvider registered#
#1.5#00145E166337002F000000070000176000042DA6D6402380#1176094489187#com.sap.tc.lm.
ctc.cul.j2eeengine.CULStartup##com.sap.tc.lm.ctc.cul.j2eeengine.CULStartup#######S
APEngine_System_Thread[impl:5]
_22##0#0#Info#1#/System/Server/CTC#Plain###...TextSourceProvider registered#
#1.5#00145E166337002F000000090000176000042DA6D6402EA5#1176094489187#com.sap.tc.lm.
ctc.cul.j2eeengine.CULStartup##com.sap.tc.lm.ctc.cul.j2eeengine.CULStartup#######S
APEngine_System_Thread[impl:5]
_22##0#0#Info#1#/System/Server/CTC#Plain###...JavaServiceProvider registered#
#1.5#00145E166337002F0000000B0000176000042DA6D6411DF4#1176094489250#com.sap.tc.lm.
ctc.cul.j2eeengine.CULStartup##com.sap.tc.lm.ctc.cul.j2eeengine.CULStartup#######S
APEngine_System_Thread[impl:5]
_22##0#0#Info#1#/System/Server/CTC#Plain###...AbapConfigurationProvider
registered#
#1.5#00145E166337002F0000000D0000176000042DA6D64262D2#1176094489343#com.sap.tc.lm.
ctc.cul.j2eeengine.CULStartup##com.sap.tc.lm.ctc.cul.j2eeengine.CULStartup#######S
APEngine_System_Thread[impl:5]
_22##0#0#Info#1#/System/Server/CTC#Plain###registerApplication2MBeanServer(sc)...#
#1.5#00145E166337002F0000000F0000176000042DA6D6428222#1176094489343#com.sap.tc.lm.
ctc.cul.j2eeengine.CULStartup##com.sap.tc.lm.ctc.cul.j2eeengine.CULStartup#######S
APEngine_System_Thread[impl:5]
_22##0#0#Info#1#/System/Server/CTC#Plain###...CULExportService registered#
#1.5#00145E166337002F000000110000176000042DA6D64292C4#1176094489343#com.sap.tc.lm.
ctc.cul.j2eeengine.CULStartup##com.sap.tc.lm.ctc.cul.j2eeengine.CULStartup#######S
APEngine_System_Thread[impl:5]
_22##0#0#Info#1#/System/Server/CTC#Plain###...CULImportService registered#
#1.5#00145E166337002F000000130000176000042DA6D642A155#1176094489359#com.sap.tc.lm.
ctc.cul.j2eeengine.CULStartup##com.sap.tc.lm.ctc.cul.j2eeengine.CULStartup#######S
APEngine_System_Thread[impl:5]
_22##0#0#Info#1#/System/Server/CTC#Plain###...CULAdminService registered#
#1.5#00145E166337002F000000150000176000042DA6D642A228#1176094489359#com.sap.tc.lm.
ctc.cul.j2eeengine.CULStartup##com.sap.tc.lm.ctc.cul.j2eeengine.CULStartup#######S
APEngine_System_Thread[impl:5]_22##0#0#Info#1#/System/Server/CTC#Plain###CTC
System started...#
#1.5#00145E166337002F000000170000176000042DA6D642A2F4#1176094489359#com.sap.tc.lm.
ctc.cul.j2eeengine.CULServiceFrame##com.sap.tc.lm.ctc.cul.j2eeengine.CULServiceFra
me#######SAPEngine_System_Thread[impl:5]
_22##0#0#Info#1#/System/Server/CTC#Plain###CUL Service started...#
#1.5#00145E166337003B000000180000176000042DA6D64B4010#1176094489921#com.sap.mona.a
pi.MonitoringAgent##com.sap.mona.api.MonitoringAgent#######SAPEngine_System_Thread
[impl:5]_49##0#0#Fatal##Plain###initAttach: java.lang.UnsatisfiedLinkError: no
jmon in java.library.path#
#1.5#00145E16633700450000000E0000176000042DA6D7196B83#1176094503468#com.sap.portal
.prt.runtime#sap.com/irj#com.sap.portal.prt.runtime#Guest#2####7a63d320e65611dba7d
100145e166337#SAPEngine_Application_Thread[impl:3]
_1##0#0#Error#1#/System/Server#Plain###Logger Definition is duplicated! please
check:lru_preemption_logger - C:
usr
sap
J10
JC11
j2ee
cluster
server0
apps
sap.com
irj
servlet_jsp
irj
root
WEB-
INF
portal
system
xml
com.sap.portal.prt.cache
logger.xml#
#1.5#00145E1663370045000000120000176000042DA6D7197EF9#1176094503468#com.sap.portal
.prt.runtime#sap.com/irj#com.sap.portal.prt.runtime#Guest#2####7a63d320e65611dba7d
100145e166337#SAPEngine_Application_Thread[impl:3]
_1##0#0#Error#1#/System/Server#Plain###Logger Definition is duplicated! please
check:SOAPLogger - C:
usr
sap
J10
JC11
j2ee
cluster
server0
apps
sap.com
irj
servlet_jsp
irj
root
WEB-
INF
portal
system
xml
com.sap.portal.runtime.application.soap
logger.xml#
#1.5#00145E16633700450000003A0000176000042DA6D7B39139#1176094513578#com.sapportals
.config.fwk.meta.ConfigClassFormatter#sap.com/irj#com.sapportals.config.fwk.meta.C
onfigClassFormatter#Guest#2####7a63d320e65611dba7d100145e166337#SAPEngine_Applicat
ion_Thread[impl:3]_1##0#0#Error##Plain###Invalid configclass file name :
[config://coll.appl.room.templatemechanism.configmeta/collaboration/template/setti
ngs/settings.cc.xml]. The file name must correspond to the configclass name
[setting] (uppercases must be escaped).#
#1.5#00145E16633700450000003B0000176000042DA6D7B3A55A#1176094513593#com.sapportals
.config.fwk.meta.ConfigClassFormatter#sap.com/irj#com.sapportals.config.fwk.meta.C
onfigClassFormatter#Guest#2####7a63d320e65611dba7d100145e166337#SAPEngine_Applicat
ion_Thread[impl:3]_1##0#0#Error##Plain###Invalid configclass file name :
[config://coll.appl.room.templatemechanism.configmeta/collaboration/template/setti
ngs/mappings/memory/memoryentry.cc.xml]. The file name must correspond to the
configclass name [mapping] (uppercases must be escaped).#
#1.5#00145E16633700450000003C0000176000042DA6D7B72184#1176094513812#com.sapportals
.config.fwk.meta.MetaConfigManager_V2#sap.com/irj#com.sapportals.config.fwk.meta.M
etaConfigManager_V2#Guest#2####7a63d320e65611dba7d100145e166337#SAPEngine_Applicat
ion_Thread[impl:3]_1##0#0#Error##Plain###[meta_v2_config://local] error while
migrating [metarchive_portal]. The configMetaArchive needs to be removed or
migrated 'manually' : ConfigException: Configuration framework system error:
"source [config://pcd/local/meta/lib] already contain the configMetaArchive."#
#1.5#00145E1663370045000001DC0000176000042DA6D8279A46#1176094521187#com.sap.portal
.RFCLogger#sap.com/irj#com.sap.portal.RFCLogger#Guest#2####7a63d320e65611dba7d1001
45e166337#SAPEngine_Application_Thread[impl:3]_1##0#0#Info##Plain###
[RFCEngineService]: AfterInit(): Try to register to portal Bridge#
#1.5#00145E1663370045000001DD0000176000042DA6D8279AEE#1176094521187#com.sap.portal
.RFCLogger#sap.com/irj#com.sap.portal.RFCLogger#Guest#2####7a63d320e65611dba7d1001
45e166337#SAPEngine_Application_Thread[impl:3]_1##0#0#Info##Plain###
[RFCEngineService]: registerToPortalBridge#
#1.5#00145E1663370045000001DE0000176000042DA6D827A13E#1176094521187#com.sap.portal
.RFCLogger#sap.com/irj#com.sap.portal.RFCLogger#Guest#2####7a63d320e65611dba7d1001
45e166337#SAPEngine_Application_Thread[impl:3]_1##0#0#Info##Plain###
[RFCEngineService]: registerToPortalBridge Ok#
#1.5#00145E1663370045000001DF0000176000042DA6D827A1B6#1176094521187#com.sap.portal
.RFCLogger#sap.com/irj#com.sap.portal.RFCLogger#Guest#2####7a63d320e65611dba7d1001
45e166337#SAPEngine_Application_Thread[impl:3]_1##0#0#Info##Plain###
[RFCEngineService]: AfterInit(): Successfully register to portal bridge#
#1.5#00145E16633700450000022F0000176000042DA6D8FAC871#1176094535031#com.sap.workfl
ow#sap.com/irj#com.sap.workflow.#Guest#2####7a63d320e65611dba7d100145e166337#SAPEn
gine_Application_Thread[impl:3]_1##0#0#Error##Plain###Object not found in lookup
of WF_DBPOOL.#
#1.5#00145E1663370045000002310000176000042DA6D8FACA66#1176094535031#com.sap.workfl
ow#sap.com/irj#com.sap.workflow.#Guest#2####7a63d320e65611dba7d100145e166337#SAPEn
gine_Application_Thread[impl:3]_1##0#0#Error##Plain###Object not found in lookup
of SAPFP4DB.#
#1.5#00145E1663370045000002330000176000042DA6D8FACF51#1176094535031#com.sap.workfl
ow#sap.com/irj#com.sap.workflow.#Guest#2####7a63d320e65611dba7d100145e166337#SAPEn
gine_Application_Thread[impl:3]_1##0#0#Error##Plain###Path to object does not
exist at java:comp, the whole lookup name is java:comp/env/jdbc/SAP/EP_PRT.#
#1.5#00145E1663370045000002370000176000042DA6D90881B8#1176094535937#com.sap.portal
.RFCLogger#sap.com/irj#com.sap.portal.RFCLogger#Guest#2####7a63d320e65611dba7d1001
45e166337#SAPEngine_Application_Thread[impl:3]_1##0#0#Info##Plain###
[RFCEngineService]: registerToRFCDispatcher Ok#
#1.5#00145E1663370045000002380000176000042DA6D90882AF#1176094535937#com.sap.portal
.RFCLogger#sap.com/irj#com.sap.portal.RFCLogger#Guest#2####7a63d320e65611dba7d1001
45e166337#SAPEngine_Application_Thread[impl:3]_1##0#0#Info##Plain###
[RFCEngineService] setFunctionCallListener: name function =
RSRD_BROADCASTING_KM_RFC; name application =
com.sap.ip.bi.broadcasting.broadcasting#
#1.5#00145E16633700450000023A0000176000042DA6D90D1644#1176094536234#com.sap.portal
.RFCLogger#sap.com/irj#com.sap.portal.RFCLogger#Guest#2####7a63d320e65611dba7d1001
45e166337#SAPEngine_Application_Thread[impl:3]_1##0#0#Info##Plain###
[RFCEngineService]: registerToRFCDispatcher Ok#
#1.5#00145E16633700450000023B0000176000042DA6D90D16BC#1176094536234#com.sap.portal
.RFCLogger#sap.com/irj#com.sap.portal.RFCLogger#Guest#2####7a63d320e65611dba7d1001
45e166337#SAPEngine_Application_Thread[impl:3]_1##0#0#Info##Plain###
[RFCEngineService] setFunctionCallListener: name function = RSRD_GET_PORTAL_USERS;
name application = com.sap.ip.bi.broadcasting.broadcasting_users#
#1.5#00145E16633700450000023C0000176000042DA6D90D2484#1176094536234#com.sap.portal
.RFCLogger#sap.com/irj#com.sap.portal.RFCLogger#Guest#2####7a63d320e65611dba7d1001
45e166337#SAPEngine_Application_Thread[impl:3]_1##0#0#Info##Plain###
[RFCEngineService]: registerToRFCDispatcher Ok#
#1.5#00145E16633700450000023D0000176000042DA6D90D24EC#1176094536234#com.sap.portal
.RFCLogger#sap.com/irj#com.sap.portal.RFCLogger#Guest#2####7a63d320e65611dba7d1001
45e166337#SAPEngine_Application_Thread[impl:3]_1##0#0#Info##Plain###
[RFCEngineService] setFunctionCallListener: name function =
RSRD_MAP_TO_PORTAL_USERS; name application =
com.sap.ip.bi.broadcasting.broadcasting_users#
#1.5#00145E16633700450000023F0000176000042DA6D90D3344#1176094536234#com.sap.portal
.RFCLogger#sap.com/irj#com.sap.portal.RFCLogger#Guest#2####7a63d320e65611dba7d1001
45e166337#SAPEngine_Application_Thread[impl:3]_1##0#0#Info##Plain###
[RFCEngineService]: registerToRFCDispatcher Ok#
I think the most important information of default trace file is : OutofMemory.
Could you please give any suggestion to avoid the server restart automaticly ?
Thanks in advance!
Best Regards,
Jianguo Chen