Re: Mod_jk and Kernel Panic - not syncing: Attempting to free lock on active lock list
Artur wrote: Hello after the weekend, Does it mean that mod_jk 1.2.18 is not using flock() function at all ? With 1.2.18 there is no kernel panic problem. I have written to RedHat support to tell them that this flock() function could be buggy. It does use flock(), but maybe with another use pattern. I'm not sure about that. Do you know when 1.2.22 version is goint to be released ? Most likely today or tomorrow. And another question. I have set logging for mod_jk to error level, but it logs every request and response time, shoudn't only errors be logged ? Sounds like you are using JkRequestLogFormat, which will additionally (unconditionally) log every request to the mod_jk log file. Normally response time is sth like 0.0500 or 0.0900 but sometimes it is 10.2345 or 15.2543 or even 90.0456. What can take so much time ? Add %D to your tomcat access log and check, if the request als take that long on tomcat (which is very likely). If yes, you need to investigate the webapp/tomcat/jvm side. Regards Artur Mladen Turk wrote: Artur Różycki wrote: Hello, We are running Red Hat Enterprise Linux ES (v. 4 for AMD64/Intel EM64T) as an Web server with Apache (2.2.4 compiled from sources) connected through mod_jk (1.2.21 compiled from sources) to tomcat server(5.5.17). This is a kernel bug related to flock With 1.2.22 we are using fcntl for locking, so it won't be observed. Regards, Mladen. - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Mod_jk and Kernel Panic - not syncing: Attempting to free lock on active lock list
Hello, We are running Red Hat Enterprise Linux ES (v. 4 for AMD64/Intel EM64T) as an Web server with Apache (2.2.4 compiled from sources) connected through mod_jk (1.2.21 compiled from sources) to tomcat server(5.5.17). Everything is installed on IBM x346 with 3GB of RAM and Xeon 3Ghz CPU. The kernel is 2.6.9-42.0.10.ELsmp from rpm package. After upgrading from mod_jk 1.2.18 to mod_jk 1.2.21, during heavy load in work hours sometimes server hangs with message: Kernel Panic - not syncing: Attempting to free lock on active lock list and it stops responding to anything. After restarting it can work for several hours without any problem but suddenly it hangs. We suspect that new mod_jk is the reason. Now we are back on mod_jk 1.2.18 and problem doesn't occur during last 30 hours. This problem occures on several identical machines (IBM x346), so it's not a hardware dependent. Below is our configuration, maybe you have any suggestions to change something for better performance. ### worker.properties worker.list=worker4,jkstatus worker.worker2.type=ajp13 worker.worker2.host=localhost worker.worker2.port=8009 worker.worker2.lbfactor=1 worker.worker2.socket_timeout=60 worker.worker2.connection_pool_timeout=300 worker.worker3.type=ajp13 worker.worker3.host=localhost worker.worker3.port=8109 worker.worker3.lbfactor=1 worker.worker3.socket_timeout=60 worker.worker3.connection_pool_timeout=300 worker.jkstatus.type=status worker.worker4.type=lb worker.worker4.sticky_session=true worker.worker4.balance_workers=worker2,worker3 ### worker.properties ### httpd.conf # # worker MPM IfModule mpm_worker_module ServerLimit 64 StartServers 20 MaxClients 960 MinSpareThreads 20 MaxSpareThreads 100 ThreadsPerChild 15 MaxRequestsPerChild 3 /IfModule ### httpd.conf # server.xml ### Connector port=8009 redirectPort=8433 secure=true connectionTimeout=0 threadPriority=25 connectionUploadTimeout=0 connectionLinger=0 maxSpareThreads=100 maxThreads=500 maxKeepAliveRequests=250 disableUploadTimeout=false uRIEncoding=ISO-8859-2 tcpNoDelay=false minSpareThreads=4 acceptCount=6 protocol=AJP/1.3 /Connector server.xml ### Thanks in advance for any help. Best regards Artur - To start a new topic, e-mail: [EMAIL PROTECTED] To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: Mod_jk and Kernel Panic - not syncing: Attempting to free lock on active lock list
Are you able to produce a stack dump (from a core) of the httpd process, which is responsible? Artur Różycki wrote: Hello, We are running Red Hat Enterprise Linux ES (v. 4 for AMD64/Intel EM64T) as an Web server with Apache (2.2.4 compiled from sources) connected through mod_jk (1.2.21 compiled from sources) to tomcat server(5.5.17). Everything is installed on IBM x346 with 3GB of RAM and Xeon 3Ghz CPU. The kernel is 2.6.9-42.0.10.ELsmp from rpm package. After upgrading from mod_jk 1.2.18 to mod_jk 1.2.21, during heavy load in work hours sometimes server hangs with message: Kernel Panic - not syncing: Attempting to free lock on active lock list and it stops responding to anything. After restarting it can work for several hours without any problem but suddenly it hangs. We suspect that new mod_jk is the reason. Now we are back on mod_jk 1.2.18 and problem doesn't occur during last 30 hours. This problem occures on several identical machines (IBM x346), so it's not a hardware dependent. Below is our configuration, maybe you have any suggestions to change something for better performance. ### worker.properties worker.list=worker4,jkstatus worker.worker2.type=ajp13 worker.worker2.host=localhost worker.worker2.port=8009 worker.worker2.lbfactor=1 worker.worker2.socket_timeout=60 worker.worker2.connection_pool_timeout=300 worker.worker3.type=ajp13 worker.worker3.host=localhost worker.worker3.port=8109 worker.worker3.lbfactor=1 worker.worker3.socket_timeout=60 worker.worker3.connection_pool_timeout=300 worker.jkstatus.type=status worker.worker4.type=lb worker.worker4.sticky_session=true worker.worker4.balance_workers=worker2,worker3 ### worker.properties ### httpd.conf # # worker MPM IfModule mpm_worker_module ServerLimit 64 StartServers 20 MaxClients 960 MinSpareThreads 20 MaxSpareThreads 100 ThreadsPerChild 15 MaxRequestsPerChild 3 /IfModule ### httpd.conf # server.xml ### Connector port=8009 redirectPort=8433 secure=true connectionTimeout=0 threadPriority=25 connectionUploadTimeout=0 connectionLinger=0 maxSpareThreads=100 maxThreads=500 maxKeepAliveRequests=250 disableUploadTimeout=false uRIEncoding=ISO-8859-2 tcpNoDelay=false minSpareThreads=4 acceptCount=6 protocol=AJP/1.3 /Connector server.xml ### Thanks in advance for any help. Best regards Artur - To start a new topic, e-mail: [EMAIL PROTECTED] To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: Mod_jk and Kernel Panic - not syncing: Attempting to free lock on active lock list
Artur Różycki wrote: Hello, We are running Red Hat Enterprise Linux ES (v. 4 for AMD64/Intel EM64T) as an Web server with Apache (2.2.4 compiled from sources) connected through mod_jk (1.2.21 compiled from sources) to tomcat server(5.5.17). This is a kernel bug related to flock With 1.2.22 we are using fcntl for locking, so it won't be observed. Regards, Mladen. - To start a new topic, e-mail: [EMAIL PROTECTED] To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
