I am not completely sure of the meaning or the interplay between slowClientQueueLimit and messageQueueLimit.
As per the documentation, they both should ideally be set to the same value, https://ignite.apache.org/releases/2.4.0/javadoc/org/apache/ignite/spi/communication/tcp/TcpCommunicationSpi.html#setSlowClientQueueLimit-int-
However when i do set that i see this in the logs, is it a minor bug in the check or should i change this?
[WARN ] 2018-06-27 22:32:18.429 [main] org.apache.ignite.spi.communication.tcp.TcpCommunicationSpi - Slow client queue limit is set to a value greater than message queue limit (slow client queue limit will have no effect) [msgQueueLimit=1024, slowClientQueueLimit=1024]
Thanks
From code the warning is correct, but javadoc is not. slowClientQueueLimit has to be less than msgQueueLimit, because when message is being prepared to sending, first are checked back pressure limits, and only then slowClientQueueLimit. If these two numbers are equal, sender thread will be blocked by back pressure before it could go to slow client check. What means client would not be dropped.
Set slowClientQueueLimit to msgQueueLimit - 1 or less, and I'll suggest community to fix the docs.
Related
I am following this guide- https://spring.io/guides/gs/messaging-jms/
I have few messages with higher priority that needs to be sent before any other message.
I have already tried following -
jmsTemplate.execute(new ProducerCallBack(){
public Object doInJms(Session session,MessageProducer producer){
Message hello1 =session.createTextMessage("Hello1");
producer.send(hello1, DeliveryMode.PERSISTENT,0,0); // <- low priority
Message hello2 =session.createTextMessage("Hello2");
producer.send(hello1, DeliveryMode.PERSISTENT,9,0);// <- high priority
}
})
But the messages are sent in order as they are in the code.What I am missing here?
Thank you.
There are a number of factors that can influence the arrival order of messages when using priority. The first question would be did you enable priority support and the second would be is there a consumer online at the time you sent the message.
There are many good resources for information on using prioritized messages with ActiveMQ, here is one. Keep in mind that if there is an active consumer online when you sent those messages then the broker is just going to dispatch them as they arrive since and the consumer will of course process them in that order.
I to want get and historize queue metrics for the "Enqueued, Dequeued an Size" (Terminology formerly met on ActiveMQ).
The moving charts provided in the management plugin are not enough for the monitoring that I need to do.
So with RabbitMQ, I'm getting data from https://rabbitmq-server:15672/api/queues/myvhost
This returns json.. for a queue, I can obtain real life production data like :
"messages":0, // for "Size"
"message_stats":{
"deliver_get":171528, // for "Dequeued"
"ack":162348,
"redeliver":9513,
"deliver_no_ack":0,
"deliver":171528,
"get":0,
"publish":51293 // for "Enqueued"
(...)
I'm in particular surprised by the publish counter:
Its value can even decrease between 2 measures done with a couple of minutes of delay ! (see sample chart around 17:00)
As you can see on my data, the deliver_get is significantly larger than the publish.
https://my-rabbitmq:15672/doc/stats.html doesn't give a lot of details that could explain what I actually notice.
Also, under the message_stats object that I obtain, I'm missing the some counters like confirm and return which could be related to the enqueuing.
Are there relationships between these metrics ? (like deliver_get + messages = redeliver + publish.. but that one doesn't work with my figures)
Is there another more detailed documentation about these metrics ?
I'm maintaining an antedeluvian Notes application which connects to a SAP back-end via a manually done 'Webservice'
The server is running Domino Release 7.0.4FP2 HF97.
The Webservice is not the more recently Webservice Consumer, but a large Java agent which is using Apache soap.jar (org.apache.soap). Below an example of the calling code.
private Call setupSOAPCall() {
Call call = new Call();
SOAPHTTPConnection conn = new SOAPHTTPConnection();
call.setSOAPTransport(conn);
call.setEncodingStyleURI(Constants.NS_URI_SOAP_ENC);
There has been a change in the SAP system which is now taking 8 minutes to complete (verified by SAP Team).
I'm getting an error message as follows:
[SOAPException: faultCode=SOAP-ENV:Client; msg=For input string: "906 "; targetException=java.lang.NumberFormatException: For input string: "906 "]
I found a blog article describing the error message quite closely:
https://thejavablog.wordpress.com/category/jmeter/
and I've come to the hypothesis that it is a timeout message that is returning to my Call object and that this timeout message is being incorrectly parsed, hence the NumberFormat Exception.
Looking at my logs I can see that there is a time difference of 62 seconds between my call and the response.
I recommended that the server setting in the server document, tab Internet Protocols/HTTP/Timeouts/Request timeouts be changed from 60 seconds to 600 seconds, and the http task restarted with
tell http restart
I've re-run the tests and I am getting the same error, and the time difference is still slightly more than 60 seconds, which is not what I was expecting.
I read Michael Rulnau's blog entry
http://www.mruhnau.net/2014/06/how-to-overcome-domino-webservice.html
which points to this APR
http://www-01.ibm.com/support/docview.wss?uid=swg1LO48272
but I'm not convinced that this would apply in this case, since there is no way that IBM would know that my Java agent is in fact making a Soap call.
My current hypothesis is that I have to use either the setTimeout() method on
org.apache.axis.client.Call
https://axis.apache.org/axis/java/apiDocs/org/apache/axis/client/Call.html
or on the org.apache.soap.transport.http.SOAPHTTPConnection
https://docs.oracle.com/cd/B13789_01/appdev.101/b12024/org/apache/soap/transport/http/SOAPHTTPConnection.html
and that the timeout value is an apache default, not something that is controlled by the Domino server.
I'd be grateful for any help.
I understand your approach, and I hope this is the correct one to solve your problem.
Add a debug (console write would be fine) that display the default Timeout then try to increase it to 10 min.
SOAPHTTPConnection conn = new SOAPHTTPConnection();
System.out.println("time out is :" + conn.getTimeout());
conn.setTimeout(600000);//10 min in ms
System.out.println("after setting it, time out is :" + conn.getTimeout());
call.setSOAPTransport(conn);
Now keep in mind that Dommino has also a Max LotusScript/Java execution time, check this value and (at least for a try) change it: http://www.ibm.com/support/knowledgecenter/SSKTMJ_9.0.1/admin/othr_servertasksagentmanagertab_r.html (it's version 9 help but this part should be identical)
I've since discovered that it wasn't my code generating the error; the default timeout for the apache axis SOAPHTTPConnetion is 0, i.e. no timeout.
I have a job that periodically does some work involving ServerXmlHttpRquest to perform an HTTP POST. The job runs every 60 seconds.
And normally it runs without issue. But there's about a 1 in 50,000 chance (every two or three months) that it will hang:
IXMLHttpRequest http = new ServerXmlHttpRequest();
http.open("POST", deleteUrl, false, "", "");
http.send(stuffToDelete); <---hang
When it hangs, not even the Task Scheduler (with the option enabled to kill the job if it takes longer than 3 minutes to run) can end the task. I have to connect to the remote customer's network, get on the server, and use Task Manager to kill the process.
And then its good for another month or three.
Eventually i started using Task Manager to create a process dump,
so i could analyze where the hang is. After five crash dumps (over the last 11 months or so) i get a consistent picture:
ntdll.dll!_NtWaitForMultipleObjects#20()
KERNELBASE.dll!_WaitForMultipleObjectsEx#20()
user32.dll!MsgWaitForMultipleObjectsEx()
user32.dll!_MsgWaitForMultipleObjects#20()
urlmon.dll!CTransaction::CompleteOperation(int fNested) Line 2496
urlmon.dll!CTransaction::StartEx(IUri * pIUri, IInternetProtocolSink * pOInetProtSink, IInternetBindInfo * pOInetBindInfo, unsigned long grfOptions, unsigned long dwReserved) Line 4453 C++
urlmon.dll!CTransaction::Start(const wchar_t * pwzURL, IInternetProtocolSink * pOInetProtSink, IInternetBindInfo * pOInetBindInfo, unsigned long grfOptions, unsigned long dwReserved) Line 4515 C++
msxml3.dll!URLMONRequest::send()
msxml3.dll!XMLHttp::send()
Contoso.exe!FrobImporter.TFrobImporter.DeleteFrobs Line 971
Contoso.exe!FrobImporter.TFrobImporter.ImportCore Line 1583
Contoso.exe!FrobImporter.TFrobImporter.RunImport Line 1070
Contoso.exe!CommandLineProcessor.TCommandLineProcessor.HandleFrobImport Line 433
Contoso.exe!CommandLineProcessor.TCommandLineProcessor.CoreExecute Line 71
Contoso.exe!CommandLineProcessor.TCommandLineProcessor.Execute Line 84
Contoso.exe!Contoso.Contoso Line 167
kernel32.dll!#BaseThreadInitThunk#12()
ntdll.dll!__RtlUserThreadStart()
ntdll.dll!__RtlUserThreadStart#8()
So i do a ServerXmlHttpRequest.send, and it never returns. It will sit there for days (causing the system to miss financial transactions, until come Sunday night i get a call that it's broken).
It is of no help unless someone knows how to debug code, but the registers in the stalled thread at the time of the dump are:
EAX 00000030
EBX 00000000
ECX 00000000
EDX 00000000
ESI 002CAC08
EDI 00000001
EIP 732A08A7
ESP 0018F684
EBP 0018F6C8
EFL 00000000
Windows Server 2012 R2
Microsoft IIS/8.5
Default timeouts of ServerXmlHttpRequest
You can use serverXmlHttpRequest.setTimeouts(...) to configure the four classes of timeouts:
resolveTimeout: The value is applied to mapping host names (such as "www.microsoft.com") to IP addresses; the default value is infinite, meaning no timeout.
connectTimeout: A long integer. The value is applied to establishing a communication socket with the target server, with a default timeout value of 60 seconds.
sendTimeout: The value applies to sending an individual packet of request data (if any) on the communication socket to the target server. A large request sent to a server will normally be broken up into multiple packets; the send timeout applies to sending each packet individually. The default value is 30 seconds.
receiveTimeout: The value applies to receiving a packet of response data from the target server. Large responses will be broken up into multiple packets; the receive timeout applies to fetching each packet of data off the socket. The default value is 30 seconds.
The KB305053 (a server that decides to keep the connection open will cause serverXmlHttpRequest to wait for the connection to close) seems like it plausibly could be the issue. But the 30 second default timeout would have taken care of that.
Possible workaround - Add myself to a Job
The Windows Task Scheduler is unable to terminate the task; even though the option is enabled to do do.
I will look into using the Windows Job API to add my self process to a job, and use SetInformationJobObject to set a time limit on my process:
CreateJobObject
AssignProcessToJobObject
SetInformationJobObject
to limit my process to three minutes of execution time:
PerProcessUserTimeLimit
If LimitFlags specifies
JOB_OBJECT_LIMIT_PROCESS_TIME, this member is the per-process
user-mode execution time limit, in 100-nanosecond ticks. Otherwise,
this member is ignored.
The system periodically checks to determine
whether each process associated with the job has accumulated more
user-mode time than the set limit. If it has, the process is
terminated.
If the job is nested, the effective limit is the most
restrictive limit in the job chain.
Although since Task Scheduler uses Job objects to also limit a task's time, i'm not hopeful that the Job Object can limit a job either.
Edit: Job objects cannot limit a process by process time - only user time. And with a process idle waiting for an object, it will not accumulate any user time - certainly not three minutes worth.
Bonus Reading
How can a ServerXMLHTTP GET request hang? (GET, not POST)
KB305053: ServerXMLHTTP Stops Responding When You Send a POST Request (which says the timeout should expire; where mine does not)
MS Forums: oHttp.Send - Hangs (HEAD, not POST)
MS Forums: ASP to test SOAP WebService using MSXML2.ServerXMLHTTP Send hangs
CC to MS Support Forums
Consider switching to a newer, supported API.
msxml6.dll using MSXML2.ServerXMLHTTP.6.0
winhttpcom.dll using WinHttp.WinHttpRequest.5.1.
The msxml3.dll library is no longer supported and is only kept around for compatibility reasons. Plus, there were a number of security and stability improvements included with msxml4.dll (and newer) that you are missing out on.
In beanstalkd
telnet localhost 11300
USING foo
put 0 100 120 5
hello
INSERTED 1
How can I know what is the priority of this job when I reserve it? And can I release it by making the new priority equals to current priority +100?
Beanstalkd doesn't return the priority with the data - but you could easily add it as metadata in your own message body. for example, with Json as a message wrapper:
{'priority':100,'timestamp':1302642381,'job':'download http://example.com/'}
The next message that will be reserved will be the next available entry from the selected tubes, according to priority and time - subject to any delay that you had requested when you originally sent the message to the queue.
Addition: You can get the priority of a beanstalk job (as well as a number of other pieces of information, such as how many times it has previously been reserved), but it's an additional call - to the stats-job command. Called with the jobId, it returns about a dozen different pieces of information. See the protocol document, and your libraries docs.