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<DIV dir=ltr align=left><SPAN class=821253413-14072008><FONT face=Arial
color=#0000ff>Cross posted for information.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=821253413-14072008><FONT face=Arial
color=#0000ff></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=821253413-14072008><FONT face=Arial
color=#0000ff>Ths subject is more for the user list than the dev'
one.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=821253413-14072008><FONT face=Arial
color=#0000ff></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=821253413-14072008><FONT face=Arial
color=#0000ff>Cheers,</FONT></SPAN></DIV><BR>
<BLOCKQUOTE style="MARGIN-RIGHT: 0px">
<DIV class=OutlookMessageHeader lang=en-us dir=ltr align=left>
<HR tabIndex=-1>
<FONT face=Tahoma><B>From:</B> rules-dev-bounces@lists.jboss.org
[mailto:rules-dev-bounces@lists.jboss.org] <B>On Behalf Of </B>9Lives
9Lives<BR><B>Sent:</B> 14 July 2008 14:33<BR><B>To:</B> Rules Dev
List<BR><B>Subject:</B> RE: [rules-dev] Multi threading usage best
practice<BR></FONT><BR></DIV>
<DIV></DIV>TnX Mike 4 the quick response.<BR> <BR>I'm afraid that u r
right regarding the through-put ;-(<BR>Using the "synchronized" method will
probably solve my problem but will damage the solution.<BR> <BR>If u have
any other thoughts on the matter i would love 2 hear
them.<BR> <BR>Regards<BR>Dotan<BR><BR><BR><BR><BR>
<HR id=EC_stopSpelling>
<BR>Subject: RE: [rules-dev] Multi threading usage best practice<BR>Date: Mon,
14 Jul 2008 14:24:02 +0100<BR>From: manstis1@ford.com<BR>To:
rules-dev@lists.jboss.org<BR><BR><BR>
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<DIV dir=ltr align=left><SPAN class=EC_055561913-14072008><FONT face=Arial
color=#0000ff>Hi,</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=EC_055561913-14072008><FONT face=Arial
color=#0000ff></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=EC_055561913-14072008><FONT face=Arial
color=#0000ff>Would synchronising on working memory effectively serialise the
effects of fireAllRules()?</FONT></SPAN></DIV>
<BLOCKQUOTE dir=ltr style="MARGIN-RIGHT: 0px">
<DIV dir=ltr align=left><SPAN class=EC_055561913-14072008><FONT
face="Courier New" color=#0000ff>...</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=EC_055561913-14072008><FONT
face="Courier New" color=#0000ff>synchronised(wm) {</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=EC_055561913-14072008><FONT
face="Courier New"> <FONT
color=#0000ff>wm.fireAllRules();</FONT></FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=EC_055561913-14072008><FONT
face="Courier New" color=#0000ff>}</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=EC_055561913-14072008><FONT
face="Courier New" color=#0000ff>...</FONT></SPAN></DIV></BLOCKQUOTE>
<DIV dir=ltr align=left><SPAN class=EC_055561913-14072008><FONT face=Arial
color=#0000ff>I don't know whether this would kill your through-put
either.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=EC_055561913-14072008><FONT face=Arial
color=#0000ff></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=EC_055561913-14072008><FONT face=Arial
color=#0000ff>Cheers,</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=EC_055561913-14072008><FONT face=Arial
color=#0000ff></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=EC_055561913-14072008><FONT face=Arial
color=#0000ff>Mike</FONT></SPAN></DIV><BR>
<BLOCKQUOTE style="MARGIN-RIGHT: 0px">
<DIV class=EC_OutlookMessageHeader lang=en-us dir=ltr align=left>
<HR>
<FONT face=Tahoma><B>From:</B> rules-dev-bounces@lists.jboss.org
[mailto:rules-dev-bounces@lists.jboss.org] <B>On Behalf Of </B>9Lives
9Lives<BR><B>Sent:</B> 14 July 2008 13:41<BR><B>To:</B>
rules-dev@lists.jboss.org<BR><B>Subject:</B> [rules-dev] Multi threading
usage best practice<BR></FONT><BR></DIV>
<DIV></DIV>Hello<BR> <BR>I'm using Drools 4.0.7 inside a mail relay
application 2 determine the operations that need 2 b executed on each
passing message.<BR>To do this i'm using the following scenario:<BR>
<OL>
<LI>
<DIV>I have a ruleBase.newStatefulSession().</DIV>
<LI>
<DIV>I have a fixed set of facts.</DIV>
<LI>
<DIV>I have a fixed set of rules.</DIV>
<LI>
<DIV>Each mailer (a thread that is handling a single message) is inserting
the message to the working memory, calls the "fireAllRules" method and
retracts the message.</DIV>
<LI>
<DIV>Rules that r executed change custom attributes in the
message.</DIV></LI></OL>Problem:<BR>I noticed that sometimes a rule can b
executed on the same message more then once.<BR> <BR>Assumption:<BR>My
guess is that because i'm working is a multi threading environment
but using a stateful session, what happens is:<BR>
<OL>
<LI>Thread A is inserting Message A.
<LI>Thread B is inserting Message B
<LI>Thread A is calling fireAllRules
<LI>Rule X is executed on messages A + B.
<LI>Thread B is calling fireAllRules
<LI>Rule X is executed on messages A + B
<LI>Thread A is retracting Message A
<LI>Thread B is retracting message B</LI></OL>Question:<BR>My goal is 2 make
sure a rule is executed only once on a single message.<BR>Any ideas on how 2
avoid the situation described
above?<BR> <BR>TnX<BR>Dotan<BR> <BR> <BR><BR>
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