Parallel processing inside EJB

Hello!
I have an EJB (Stateless session) that needs to call three other EJBs to perform some actions.
Right now, the EJB calls the others performing action A. If A is successfull performs B and then C.
I would like to perform A. If A is successfull, perform B and C simultaneously.
If this was a normal Java program, I would execute class A and then launch as threads B and C, getting notifications on complete.
I read that threading shouldn't be used in EJB's. So, is it possible to call two beans simultaneously from another bean?
For those thinking JMS, I also thought about that but would like to do it "the old Java way".
Pointers to docs, comments, etc are appreciated. Even flames! ;)
Thank you for your time!
HappyGuy

Why can't u incorporate the 3 other actions in the same EJB. What holds U ?
And If it is very much required, Then go ahead Have the other 3 Actions to return boolean.
Let The X Bean on condition Lookup the Bean A and Bean A's Method.
Since return type is boolean,
Decide to invoke B and even when B return's true Then invoke C.
Even tho u can invoke 2 Bean ( B & C) simultaneously, the control will go the first ( B or C) and then ithe control will follow down.
Its always better to have check for the boolean value and then decide,
Solution Ok ,
Kindly Let Me Know.

Similar Messages

Parallel processing of mass data : sy-subrc value is not changed

Hi,
I have used the Parallel processing of mass data using the "Start New Task" . In my function module I am handling the exceptions and finally raise the application specific old exception to be handled in my main report program. Somehow the sy-subrc is not getting changed and always returns 0 even if the expection is raised.
Can anyone help me about the same.
Thanks & Regards,
Nitin

Hi Silky,
I've build a block of code to explain this.
DATA: ls_edgar TYPE zedgar,
        l_task(40).
DELETE FROM zedgar.
COMMIT WORK.
l_task = 'task1'.
ls_edgar-matnr = '123'.
ls_edgar-text = 'qwe'.
CALL FUNCTION 'Z_EDGAR_COMMIT_ROLLBACK' STARTING NEW TASK l_task PERFORMING f_go ON END OF TASK
    EXPORTING
      line = ls_edgar.
l_task = 'task2'.
ls_edgar-matnr = 'abc'.
ls_edgar-text = 'def'.
CALL FUNCTION 'Z_EDGAR_COMMIT_ROLLBACK' STARTING NEW TASK l_task PERFORMING f_go ON END OF TASK
    EXPORTING
      line = ls_edgar.
l_task = 'task3'.
ls_edgar-matnr = '456'.
ls_edgar-text = 'xyz'.
CALL FUNCTION 'Z_EDGAR_COMMIT_ROLLBACK' STARTING NEW TASK l_task PERFORMING f_go ON END OF TASK
    EXPORTING
      line = ls_edgar.
*&      Form f_go
FORM f_go USING p_c TYPE ctype.
RECEIVE RESULTS FROM FUNCTION 'Z_EDGAR_COMMIT_ROLLBACK' EXCEPTIONS err = 2.
IF sy-subrc = 2.
*this won't affect the LUW of the received function
    ROLLBACK WORK.
ELSE.
*this won't affect the LUW of the received function
    COMMIT WORK.
ENDIF.
ENDFORM.                    "f_go
and the function is:
FUNCTION z_edgar_commit_rollback.
*"*"Interface local:
*" IMPORTING
*"     VALUE(LINE) TYPE ZEDGAR
*" EXCEPTIONS
*"      ERR
MODIFY zedgar FROM line.
IF line-matnr CP 'a*'.
*comment raise or rollback/commit to test
*    RAISE err.
    ROLLBACK WORK.
ELSE.
    COMMIT WORK.
ENDIF.
ENDFUNCTION.
ok.
In your main program you have a Logical Unit of Work (LUW), witch consists of an application transaction and is associated with a database transaction. Once you start a new task, your creating an independent LUW, with it's own database transaction.
So if you do a commit or rollback in your function the effect is only on the records your processing in the function.
There is a way to capture the event when this LUW concludes in the main LUW. That is the PERFORMING whatever ON END OF TASK. In there you can get the result of the function but you cannot commit or rollback the LUW from the function since it already have implicitly happened at the conclusion of the funtion. You can test it by correctly comment the code I've supplied.
So, if you want to rollback the LUW of the function you better do it inside it.
I don't think it matches exactly your question, maybe it lead you on the right track. Give me more details if it doesn't.
Hope it helps,
Edgar

How to achieve parallel processing in a single request?

Hi all,
I have a method in a Session EJB that will perform some business logic before it returns an answer to the client. The logic it will perform is to collect data from the applications database and two external systems, before sending all data to a third external system to get a response and send it back to the client. Each external system is quite slow so I would like to do all the collecting of data concurrent, parallel processing. How should I handle this? I'm not allowed to create my own threads in EJB's. Can I use MDB in some way? To the calling client this should be a synchronous call...
Greatfull for any suggestions
Cheers
Anders =)

Usually, the request is received by a component located in the web container, such as by an HTTP request (including Web Services). This component is able to start threads to allow parallel processing. Now, if for some reason the request arrives directly at EJB level and that you cannot move its receiver to web component, I think JMS is not a viable solution because you will switch to asynchronous processing and you have no way to make your EJB wait for the responses while preserving the client request (waiting implies programmatic life cycle management, which is forbidden in EJB container). Maybe a resource adapter (JCA) can bring a solution. A resource adapter acts as a datasource (a datasource is a specialization of a resource adapter) and thus it is a logical way to implement an adapter to an external, eventually non-J2EE, resource, as the name implies :) But I don't have enough knowledge in JCA to be sure of this.
Hope it helps.
Bruno Collet
http://www.practicalsoftwarearchitect.com

Parallel processing using ABAP objects

Hello friends,
                    I had posted in the performance tuning forum , regarding a performance issue problem , I am reposting it as it involves OO concept .
the link for the previous posting
Link: [Independent processing of elements inside internal table;
Here is the scenario,
I have a internal table with 10 records(indepentent) , and i need to process them .The processing of one record doesnt have any influence on the another . When we go for loop , the performance issue is that , the 10 th record has to wait until the 9 records get processed even though there is no dependency on the output.
Could some one tell a way out to improve the performance..
If i am not clear with the question , i would explain it still clearer...
A internal table has 5 numbers , say( 1,3,4,6,7)
we are trying to find square of each number ,,,
If it is a loop the finding of suare of 7 has to wait until 6 is getting completed and it is waste of time ...
This is related to parallel processing , I have refered to parallel processing documents,But I want to do this conceptually ..
I am not using conventional procedural paradigm but Object orientedness...I am having a method which is performing this action .What am I supposed to do in that regard.
Comradely ,
K.Sibi

Hi,
As examplified by Edward, there is no RFC/asynchronous support for Methods of ABAP Objects as such. You would indeed need to "wrap" your method or ABAP Object in a Function Module, that you can then call with the addition "STARTING NEW TASK". Optionally, you can define a Method that will process the results of the Function Module that is executed asynchronously, as demonstrated as well in Edward's program.
You do need some additional code to avoid the situation where your program takes all the available resources on the Application Server. Theoretically, you cannot bring the server or system down, as there is a system profile parameter that determines the maximum number of asynchronous tasks that the system will allow. However, in a productive environment, it would be a good idea to limit the number of asynchronous tasks started from your program so that other programs can use some as well.
Function Group SPBT contains a set of Function Modules to manage parallel processing. In particular, FM SPBT_INITIALIZE will "initialize" a Server Group and return the maximum number of Parallel Tasks, as well as the number of free ones at the time of the initialization. The other FM of interest is SPBT_GET_CURR_RESOURCE_INFO, that can be called after the Server Group has been initialized, whenever you want to "fork" a new asynchronous task. This FM will give you the number of free tasks available for Parallel Processing at the time of calling the Function Module.
Below is a code snippet showing how these Function Modules could be used, so that your program always leaves a minimum of 2 tasks for Parallel Processing, that will be available for other programs in the system.
      IF md_parallel IS NOT INITIAL.
        IF md_parallel_init IS INITIAL.
*----- Server Group not initialized yet => Initialize it, and get the number of tasks available
          CALL FUNCTION 'SPBT_INITIALIZE'
          EXPORTING
            GROUP_NAME                           = ' '
            IMPORTING
              max_pbt_wps                          = ld_max_tasks
              free_pbt_wps                         = ld_free_tasks
            EXCEPTIONS
              invalid_group_name                   = 1
              internal_error                       = 2
              pbt_env_already_initialized          = 3
              currently_no_resources_avail         = 4
              no_pbt_resources_found               = 5
              cant_init_different_pbt_groups       = 6
              OTHERS                               = 7.
          md_parallel_init = 'X'.
        ELSE.
*----- Server Group initialized => check how many free tasks are available in the Server Group
      for parallel processing
          CALL FUNCTION 'SPBT_GET_CURR_RESOURCE_INFO'
            IMPORTING
              max_pbt_wps                 = ld_max_tasks
              free_pbt_wps                = ld_free_tasks
            EXCEPTIONS
              internal_error              = 1
              pbt_env_not_initialized_yet = 2
              OTHERS                      = 3.
        ENDIF.
        IF ld_free_tasks GE 2.
*----- We have at leasr 2 remaining available tasks => reserve one
          ld_taskid = ld_taskid + 1.
        ENDIF.
    ENDIF.
You may also need to program a WAIT statement, to wait until all asynchronous tasks "forked" from your program have completed their processing. Otherwise, you might find yourself in the situation where your main program has finished its processing, but some of the asynchronous tasks that it started are still running. If you do not need to report on the results of these asynchronous tasks, then that is not an issue. But, if you need to report on the success/failure of the processing performed by the asynchronous tasks, you would most likely report incomplete results in your program.
In the example where you have 10 entries to process asynchronously in an internal table, if you do not WAIT until all asynchronous tasks have completed, your program might report success/failure for only 8 of the 10 entries, because your program has completed before the asynchronous tasks for entries 9 and 10 in your internal table.
Given the complexity of Parallel Processing, you would only consider it in a customer program for situations where you have many (ie, thousands, if not tens of thousands) records to process, that the processing for each record tends to take a long time (like creating a Sales Order or Material via BAPI calls), and that you have a limited time window to process all of these records.
Well, whatever your decision is, good luck.

Java Proxy Generation not working - Support for Parallel Processing

Hi Everyone,
As per SAP Note 1230721 - Java Proxy Generation - Support for Parallel Processing, when we generate a java proxy from an interface we are supposed to get 2 archives (one for serial processing and another suffixed with "PARALLEL" for parallel processing of jaav proxies in JPR).
https://websmp230.sap-ag.de/sap(bD1lbiZjPTAwMQ==)/bc/bsp/spn/sapnotes/index2.htm?numm=1230721
We are on the correct patch level as per the Note, however when we generate java proxy from the IR for an outbound interface, it genrates only 1 zip archive (whose name we ourselves provide in the craete new archive section). This does not enable the parallel processsing of the messages in JPR.
Could you please help me in this issue, and guide as to how archives can be generated for parallel processing.
Thanks & Regards,
Rosie Sasidharan.

Hi,
Thanks a lot for your reply, Prateek.
I have already checked SAP Note 1142580 - "Java Proxy is not processing messages in parallel" where they ask to modify the ejb-jar.xml. However, on performing the change in ejb-jar.xml and while building the EAR, I get the following error:
Error! The state of the source cache is INCONSISTENT for at least one of the request DCs. The build might produce incorrect results.
Then, on going through the SAP Note 1142580 again, I realised that the SAP Note 1230721 also should be looked onto which will be needed for generating the Java proxy from Message Interfaces in IR for parallel processing.
Kindly help me if any of you have worked on such a scenario.
Thanks in advance,
Regards,
Rosie Sasidharan.

"Parallel" process

I don't think I ever got this answered..I'm running a functional test (LV2014..Win 7..DAQ6229) In the functional test.vi is a flat seq structure. In each of these seq's is a subvi... subvi1 then subvi2 etc. Each of these subvis I use the DAQ to measure DIO/voltages...etc. to do my UUT testing. Is there a way in ethier the functional test.vi or the subvis to monintor a boolean which stops the functional vi? Just looking for a way to have the DAQ running its thing...running the test ..and monitor a door switch ( the boolean) so that if the user opens the door to the test set it stops the test and turns on a Software LED that I've put on the front panel GUI of functional test. I know how to implement the boolean..I know how to implement the functional tests. I just don't know how to combined them so that they are both running simutaneously.
Thanks..
Solved!
Go to Solution.

There are two questions here. One is "How do I get an immediate response to a change, either to a control or to an instrument reading?", and the other is "How do I synchronize the activities of two parallel processes?"
The first can be handled by an Event structure residing inside a While loop. This is something that patiently "waits" for one or more of the Events it is programmed to recognize. These are typically changes in the value of a Front Panel control, or "signalling changes" to a LabVIEW control or indicator (this means that you change the value in LabVIEW, but "signal" that the value changed).
There are numerous ways to get two parallel processes to exchange information. If you want to control the second process (such as to stop it), you need one or more "points of intervention". Unfortunately, if you have your process-to-be-controlled structured as a long, single sequence, figuring out an intuitive way of "interrupting" it can be tricky.
One thing you can do (given your existing architecture) is to look at each of the sub-processes (which I gather reside in sub-VIs). Is there a point within them that, if you had a "Stop" VI that returned a True value, would cause the sub-process to immediately exit, and that if Stop were true when it started, would again cause it to exit? [This is sometimes called a VI Global or a Functional Global Variable].
If this is the case, write yourself a Stop VI that contains a While loop with an uninitialize Shift Register holding a Boolean value (and initially False, by default). Wire the output to a Boolean Indicator called Stop, with a Boolean input called "Set Stop". Inside, put a Case statement such that if Set Stop is ever True, it sets the Shift Register (and thus Stop) to True.
In your Event structure, if a Stop condition appears, call the Stop VI with True wired to Set Stop. In each of your sub-VIs, call Stop in such a way that if it ever becomes True, the sub-VI exits (doing a safe shutdown, if necessary).
Note that you can have multiple Stop VIs sprinkled around your code, and even within a sub-VI -- you need to find the "vulnerable" points that are accessed sufficiently frequently to allow Stop to have an effect.
I'll leave it to others to discuss restructuring the entire top-level program (a single sequence is not a good way to do this, if for no other reason than it is absolutely inflexible ...).
Bob Schor

Parallel process run independently, but do not stop when vi completes

So I posted a problem yesterday about getting 'elapsed time' express vi to provide updates from a sub-vi to the calling vi. It was suggested that I create a parallel process in the sub-vi that will run the elapsed time function at the same time the other processes are running. I tried to implement this idea, but ran into a problem. The elapsed time process is a While loop paralleled with the main While loop in the sub-vi, It updates every second, based on my time delay, and when I view the running sub-vi, the elapsed time indicator is updating as it should. The calling vi, however, is not seeing these updates. I have wired an indicator to the sub-vi icon, but does not change until the sub-vi finishes.
Also, the other problem with the parallel process is that it runs forever, regardless of the other loop finishing. I have tried to wire an or'd bool to the stop inside the While loop, but when I do that, the elapsed time process does not start.
I have tried data binding a shared variable in the project, and then dragging that to my calling vi, but again I get no updates on the elapsed time.
Any ideas????

A VI must finish looping before it has an available output (the terminal on the sub-vi icon). Research how to communicate between loops. What you are doing can be accomplished with Notifiers (that's what I'd use), Queues, or Global/Shared Variables.
Your issues appear to be due to a lack of understanding of the LabVIEW data-flow paradigm. Check out the Producer / Consumer example. Post code here and see if one of us can give more guidance.
Richard

Need help with parallel process in background; not able to call FM in bgnd

Hello,
I am trying since 2 days to solve the issue of parallel process in background without using FPP.
For which I want to call function module of class method in new task but to be processed by background process and not dialog.
I searched so many websites but everyone has suggesteed to 'call function in background task' . But the fact is the processing of function happens by dailog process even in this case.
I want to loop at table and call FM or class method inside each loop.
Kindly suggest me how can I call function or class method in new task in everycall and prcoess it in background.
thanks

Balaji,
Is the name of the button between single or double quotes?
Regards,
Dan
Blog: http://DanielMcGhan.us/
Work: http://SkillBuilders.com/

Parallel processing in OSB

Hi everyone,
I need to implement parallel processing in the OSB. I have a proxy service which implements a request reply pattern over JMS. This service needs to invoke three such services (request-reply over JMS) in parallel and aggregate the result and send it as a reply. How can I do this in OSB?
I have looked at the Split-Join element but it seems to only support web services. Is that correct?
Best regards,
Dimo

>
Thank you for the fast reply. Wrapping in web services has probably relatively high performance impact - I need to wrap my payload in SOAP, send it via HTTP, receive it over HTTP, parse the SOAP envelope, extract the payload and then send it via JMS. And the same steps in the reverse order to send the response. Seems like a lot of overhead to me.
>
You don't have to do all of that. If you wrap your JMS-based services using WSDL-based service with local transport, then you avoid all HTTP communication because processing stays inside OSB.
>
Isn't there any other way to parallelize the execution - the application is processing synchronous requests from a voice frontend and it should be very responsive. Does anyone know how much overhead exactly goes into the whole SOAP wrapping and unwrapping?
>
I don't know of any other way for this case. Maybe someone else will bring something better.
I have never measured SOAP overhead since for my business services it is only insignificant fraction of whole processing time. I would expect SOAP overhead to be not far from JMS overhead. Especially when XML is used as a payload.

Issue in completing the block step for parallel processing

Hi,
i have created a workflow where in i have used a block step to send workitems to multiple agents. I have used parallel processing in block step. Number of agents are determined in the runtime. Lets say i have two items in my multiple line container( two agent id). Now inside block statement i have put user decesion step. So at the same time workitems goes to the two approver for approval. When both approver take the decesion after that also command is not coming out of the block step. I want the command to be out of block step after this and goes to the next step of workflow.
Please suggest any helpful solution for it.
Regards,
Smit Shah

I think theremust be a binding problem , the binding must be some thing like the below
&USERID[&_WF_PARFOREACH_INDEX&]& ----->&_USERID_LINE&
of the block step from WF container to Block Conatiner. Because when I checked in my system it is behaving as you want., I also include one Decision step inside the block, and then hard coded the userid values int the table USERID and made the above binding and it ia working fine and in the Decision Agent I mentiond the EXPRESSION and assigned the value &_USERID_LINE&

Parallel Processing Issue : call function starting new task

Hi
I am using the parallel processing functionality using the call function new task destination in group default Performing on end of task inside a loop ( i am splitting the internal table )
However when i am debugging the code, i am able to see the function module( it opens a new session in debugging ) , and i see that new task is started after the RFC Function module is executed .
How is this parallel processing ? I mean the new task starts after control returns back to main program , after the execution of the RFC FM.
I thought the idea was to have the same FM executing in multi threads. So that time is saved.

Thanks for the answers.
There were too many complications in the 'call function in new task ' option.
So we are trying it with the job submit option. So we are splitting up the data into smaller tables and submiting it with this statement : Submit 'prog' with selection-table 's_sel' via job 'job' and return .
Thanks

Parallel Processing : Unable to capture return results using RECIEVE

Hi,
I am using parallel processing in one of my program and it is working fine but I am not able to collect return results using RECIEVE statement.
I am using
CALL FUNCTION <FUNCTION MODULE NAME>
STARTING NEW TASK TASKNAME DESTINATION IN GROUP DEFAULT_GROUP
PERFORMING RETURN_INFO ON END OF TASK
and then in subroutine RETURN_INFO I am using RECEIVE statement.
My RFC is calling another BAPI and doing explicit commit as well.
Any pointer will be of great help.
Regards,
Deepak Bhalla
Message was edited by: Deepak Bhalla
I used the wait command after rfc call and it worked additionally I have used Message switch in Receive statement because RECIEVE statement was returing sy-subrc 2.

Not sure what's going on here. Possibly a corrupt drive? Or the target drive is full?
Try running the imagex command manually from a F8 cmd window (in WinPE)
"\\OCS-MDT\CCBShare$\Tools\X64\imagex.exe" /capture /compress maximum C: "\\OCS-MDT\CCBShare$\Captures\CCB01-8_15_14.wim" "CCB01CDrive" /flags ENTERPRISE
Keith Garner - Principal Consultant [owner] -
http://DeploymentLive.com

Parallel Processing and Capacity Utilization

Dear Guru's,
We have following requirement.
Workcenter A Capacity is 1000.   (Operations are similar)
Workcenter B Capacity is 1500.   (Operations are similar)
Workcenter C Capacity is 2000.   (Operations are similar)
1) For Product A: Production Order Qty is 4500. Can we use all workcenter as a parallel processing through Routing.
2) For Product B: Production Order Qty is 2500. Can we use only W/C A and B as a parallel processing through Routing.
If yes, plz explain how?
Regards,
Rashid Masood

May be you can create a virtual WC VWCA=ABC (connected with a hierarchy with transaction CR22) and another VWCB=A+B and route your products to each VWC

Parallel processing open items (FPO4P)

Hello,
I have a question about transaction FPO4p (parallel processing of open items).
When saving the parameters the following message always appears : "Report cannot be evaluated in parallel". The information details tells that when you use a specific parallel processing object, you also need to use that field to sort on.
I my case I use the object GPART for parallel processing (see tab technical settings). In the tab output control I selected a line layout which is sorted by business partner (GPART). Furthermore no selection options are used.
Does anyone know why the transaction cannot save the parameters and shows the error message specified above. I really don't know what goes wrong.
Thank you in advance.
Regards, Ramon.

Ramon
Apply note 1115456.
Maybe that note can help you
Regards
Arcturus

How to do parallel processing with dynamic internal table

Hi All,
I need to implement parallel processing that involves dynamically created internal tables. I tried doing so using RFC function modules (using starting new task and other such methods) but didn't get success this requires RFC enabled function modules and at the same time RFC enabled function modules do not allow generic data type (STANDARD TABLE) which is needed for passing dynamic internal tables. My exact requirement is as follows:
1. I've large chunk of data in two internal tables, one of them is formed dynamically and hence it's structure is not known at the time of coding.
2. This data has to be processed together to generate another internal table, whose structure is pre-defined. But this data processing is taking very long time as the number of records are close to a million.
3. I need to divide the dynamic internal table into (say) 1000 records each and pass to a function module and submit it to run in another task. Many such tasks will be executed in parallel.
4. The function module running in parallel can insert the processed data into a database table and the main program can access it from there.
Unfortunately, due to the limitation of not allowing generic data types in RFC, I'm unable to do this. Does anyone has any idea how to implement parallel processing using dynamic internal tables in these type of conditions.
Any help will be highly appreciated.
Thanks and regards,
Ashin

try the below code...
DATA: w_subrc TYPE sy-subrc.
DATA: w_infty(5) TYPE c.
data: w_string type string.
FIELD-SYMBOLS: <f1> TYPE table.
FIELD-SYMBOLS: <f1_wa> TYPE ANY.
DATA: ref_tab TYPE REF TO data.
CONCATENATE 'P' infty INTO w_infty.
CREATE DATA ref_tab TYPE STANDARD TABLE OF (w_infty).
ASSIGN ref_tab->* TO <f1>.
* Create dynamic work area
CREATE DATA ref_tab TYPE (w_infty).
ASSIGN ref_tab->* TO <f1_wa>.
IF begda IS INITIAL.
    begda = '18000101'.
ENDIF.
IF endda IS INITIAL.
    endda = '99991231'.
ENDIF.
CALL FUNCTION 'HR_READ_INFOTYPE'
    EXPORTING
      pernr           = pernr
      infty           = infty
      begda           = '18000101'
      endda           = '99991231'
    IMPORTING
      subrc           = w_subrc
    TABLES
      infty_tab       = <f1>
    EXCEPTIONS
      infty_not_found = 1
      OTHERS          = 2.
IF sy-subrc <> 0.
    subrc = w_subrc.
ELSE.
ENDIF.

Parallel processing inside EJB

Similar Messages

Maybe you are looking for