How maxMessages property affects the MDB?
For example:
#ActivationConfigProperty(propertyName = "maxMessages", propertyValue="5").
How would this value affect if maxSessions is 10?
The JBoss docs are a bit wooly on this, they say MaxMessages is defined as
The number of messages to wait for
before attempting delivery of the
session, each message is still
delivered in a separate transaction
(default 1)
I think you were wondering if it affects the number of threads or concurrent sessions than can pass through the MDB at one time, but it seems this parameter is not related to that behaviour, and so there's no conflict.
I think you're confused, maxSessions refer to the the maximum number of JMS sessions that can concurrently deliver messages to MDB.
In the xml confi file standardjboss.xml you'd set MaximumSize to set the number of concurrent messages. In this case I've set it to 150. This affects all MDBs, however.
<invoker-proxy-binding>
<name>message-driven-bean</name>
<invoker-mbean>default</invoker-mbean>
<proxy-factory>org.jboss.ejb.plugins.jms.JMSContainerInvoker</proxy-factory>
<proxy-factory-config>
<JMSProviderAdapterJNDI>DefaultJMSProvider</JMSProviderAdapterJNDI>
<ServerSessionPoolFactoryJNDI>StdJMSPool</ServerSessionPoolFactoryJNDI>
<CreateJBossMQDestination>true</CreateJBossMQDestination>
<!-- WARN: Don't set this to zero until a bug in the pooled executor is fixed -->
<MinimumSize>1</MinimumSize>
**<MaximumSize>150</MaximumSize>**
<KeepAliveMillis>30000</KeepAliveMillis>
<MaxMessages>1</MaxMessages>
<MDBConfig>
<ReconnectIntervalSec>10</ReconnectIntervalSec>
<DLQConfig>
<DestinationQueue>queue/DLQ</DestinationQueue>
<MaxTimesRedelivered>200</MaxTimesRedelivered>
<TimeToLive>0</TimeToLive>
</DLQConfig>
</MDBConfig>
</proxy-factory-config>
</invoker-proxy-binding>
Related
I am trying to debug an issue related to keep-alives/connection resets and found that tomcat documentation says:
socket.soKeepAlive:
(bool)Boolean value for the socket's keep alive setting (SO_KEEPALIVE). JVM default used > if not set.
This is not set by the application I am debugging. Is there a way to figure out the default the jvm is using? (For instance by inspecting a system property?)
I cannot test out the behavior by inspecting the actual keep alive behavior since I don't have access to the VM.
Answering on my own based on more research and experimentation.
Default value of socket.soKeepAlive: From the JVM docs for SocketOptions.SO_KEEPALIVE:
The initial value of this socket option is FALSE. The socket option may be enabled or disabled at any time.
Also to note:
When the SO_KEEPALIVE option is enabled the operating system may use a keep-alive mechanism to periodically probe the other end of a connection
From what I understood, this would mean tomcat would not probe clients to check if an established connection is active by default
Default Value of keepAliveTimeout: The default value is to use the value that has been set for the connectionTimeout attribute
In my case this was not being reflected. connectionTimeout was set to 10 seconds, but still tomcat responses had keep alive headers set to only 5 seconds.
However, I found that the application authors also set an attribute called socket.soTimeout to 5 seconds which tomcat describes as:
This is equivalent to standard attribute connectionTimeout.
I found that when both conncetionTimeout and socket.soTimeout are set, socket.soTimeout takes precedence since changing the socket.soTimeout value caused the values returned by keep alive headers to change accordingly.
I am trying to finetune hystrix threadpool core size and max size. For that I need to know and plot the number of active threads at anytime in the pool. Is there a way to do so?
Is this the right way?
HystrixThreadPoolKey hystrixThreadPoolKey = new HystrixThreadPoolKey() {
#Override
public String name() {
return threadPoolKey;
}
};
HystrixThreadPoolMetrics hystrixThreadPoolMetrics = HystrixThreadPoolMetrics.getInstance(hystrixThreadPoolKey);
log.info("Hystrix active threads: {}", hystrixThreadPoolMetrics.getCurrentActiveCount().toString());
I am not sure because when I use this I get active thread count as 0, when the corePoolSize setting is 10.
This code works fine (after putting a null check for the time till no request is made). But the right way should be to use Netflix's servo.
Netflix Announcement
How to Use
Quoting some part from the announcement:
Servo is designed to make it easy for developers to export metrics from their application code, register them with JMX, and publish them to external monitoring systems
(Also active thread pool size can be less than the core size)
is there anyway to set request time-out while sending message from initiator ??
we had a issue where we got late reply from acceptor and application went in not responsive mode. issue can be with network delay or etc. but I think it will be good if we can set time-out option here.
Seeing with Application call back didn't find anything .
I want to set time-out option with SendToTarget API,,
any suggestion
Did you add CheckLatency and MaxLatency in your config file and confirmed ?
CheckLatency If set to Y, messages must be received from the counterparty within a defined number of seconds (see MaxLatency). It is useful to turn this off if a system uses localtime for it's timestamps instead of GMT.
MaxLatency If CheckLatency is set to Y, this defines the number of seconds latency allowed for a message to be processed. Default is 120. positive integer
I'm experiencing the same problem using QuickFix /n
Looking at the source code for version 1.4 the section that reads those settings from the configuration file is commented out and replaced with hard coded default values.
// FIXME to get from config if available
session.MaxLatency = 120;
session.CheckLatency = true;
When the quickfix initiator reconnects at startTime (defined in config) it deletes the files with sequence number, but does not set ResetSeqNumFlag to Y, and the server replies with a Logout message with text "seq msg number to low ..."
Is there a way to set ResetSeqNumFlag = Y only for this behavior? I don`t want to reset the sequence on every log-on.
This appears to be a QuickFIX/J quirk (some might consider it a bug). If ResetOnLogon=N then no ResetSeqNumFlag=Y is sent when the session start time triggers a logon. If ResetOnLogon=Y, the ResetSeqNumFlag=Y is sent on every logon. I believe this is not a big problem in practice because participants in a FIX session typically reset their sequence numbers locally after a session ends (logically ends at the end time, not a connection disconnect).
If you want to slightly modify the source code to implement this behavior, you'd modify the quickfix.Session next() method. You could add a local flag that indicates a session has restarted (per the schedule as determined by checkSessionTime()). Pass that flag to generateLogon() and that method would use it to determine when to send ResetSeqNumFlag=Y regardless of the ResetOnLogon configuration.
I don`t want to reset the sequence on every log-on.
Then don't do it! Set ResetOnLogon=N.
At StartTime, the session will reset sequence numbers always. If ResetOnLogon=N, then they won't reset again until the next StartTime.
The initiator and acceptor should always have matching ResetOnXXX settings.
What you are asking cannot, should not be done. You start you engine with some config and then you change the config while running. If something goes wrong it will be very difficult to pinpoint what started the issue.
Instead of doing ResetSeqNumFlag = Y try adding ResetOnLogon=Y in your config for the acceptor side(that is if you have control over it) or ResetOnLogout=Y / ResetOnDisconnect=Y in your initiator config file. That would be much easier and changing config while running, is possibly not the best solution.
Your logout(disconnect can happen anytime) will happen anyways at EndTime anyways and should be easier for your application.
I have a daemon process that I wrote being executed by SMF. The problem is when an error occurs, I have fail code and then it will need to restart from scratch. Right now it is sending sys.exit(0) (Python), but SMF keeps throwing it in maintenance mode.
I've worked with SMF enough to know that it sometimes auto-restarts certain services (and lets others fail and have you deal with them like this). How do I classify this process as one that needs to auto-restart? Is it an SMF setting, a method of failing, what?
Manpage
Solaris uses a combination of startd/critical_failure_count and startd/critical_failure_period as described in the svc.startd manpage:
startd/critical_failure_count
startd/critical_failure_period
The critical_failure_count and critical_failure_period properties together specify the maximum number of service failures allowed in a given time interval before svc.startd transitions the service to maintenance. If the number of failures exceeds critical_failure_count in any period of critical_failure_period seconds, svc.startd will transition the service to maintenance.
Defaults in the source code
The defaults can be found in the source, the value depends on whether the service is "wait style":
if (instance_is_wait_style(inst))
critical_failure_period = RINST_WT_SVC_FAILURE_RATE_NS;
else
critical_failure_period = RINST_FAILURE_RATE_NS;
The defaults are either 5 failures/10 minutes or 5 failures/second:
#define RINST_START_TIMES 5 /* failures to consider */
#define RINST_FAILURE_RATE_NS 600000000000LL /* 1 failure/10 minutes */
#define RINST_WT_SVC_FAILURE_RATE_NS NANOSEC /* 1 failure/second */
These variables can be set in the SMF as properties:
<service_bundle type="manifest" name="npm2es">
<service name="site/npm2es" type="service" version="1">
...
<property_group name="startd" type="framework">
<propval name='critical_failure_count' type='integer' value='10'/>
<propval name='critical_failure_period' type='integer' value='30'/>
<propval name="ignore_error" type="astring" value="core,signal" />
</property_group>
...
</service>
</service_bundle>
TL;DR
After checking against the startd values, If the service is "wait style", it will be throttled to a max restart of 1/sec, until it no longer exits with a non-cfg error. If the service is not "wait style" it will be put into maintenance mode.
Presuming a normal service manifest, I would suspect that you're dropping into maintenance because SMF is restarting you "too quickly" (which is a bit arbitrarily defined). svcs -xv should tell you if that is the case. If it is, SMF is restarting you, and then you're exiting again rapidly and it's decided to give up until the problem is fixed (and you've manually svcadm clear'd it.
I'd wondered if exiting 0 (and indicating success) may cause further confusion, but it doesn't appear that it will.
I don't think Oracle Solaris allows you to tune what SMF considers "too quickly".
You have to create a service manifest. This is more complicated than not. This has example manifests and documents the manifest structure.
http://www.oracle.com/technetwork/server-storage/solaris/solaris-smf-manifest-wp-167902.pdf
As it turns out, I had two pkills in a row to make sure everything was terminated correctly. The second one, naturally, was exiting something other than 0. Changing this to include an exit 0 at the end of the script solved the problem.