6:48 a.m.
Hello folks,
I'm experiencing some odd behaviour from Drools (or maybe the Eclipse
compiler) when load-testing my application, and wondered if anyone
else had experienced the same issue. I have a web service which, for
every request, loads in rules from the database, creates a
org.drools.lang.descr.PackageDescr and then uses this to create a
org.drools.rule.Package. The code is something like:
PackageBuilderConfiguration conf = new PackageBuilderConfiguration();
PackageBuilder builder = new PackageBuilder(conf);
PackageDescr packageDescr = new PackageDescr("MyRulebaseName");
populatePackageDescr(packageDescr);
builder.addPackage(packageDescr);
Package _package = builder.getPackage();
return _package;
This code gets run every request. The populatePackageDescr() method
adds imports, globals, functions and rules to the PackageDescr. My
load-test just repeatedly calls the same rulebase, so
populatePackageDescr() will be doing exactly the same thing for each
request. Occasionally (normally once or twice per 100 requests) I get
a rule compilation error (the exact error varies from request to
request) whereas most of the time the same rule compiles fine. This
makes me suspect a thread-safety issue in either the PackageBuilder or
the compiler (I'm using the eclipse compiler).
Initially, I suspected a problem in my
populatePackageDescr(packageDescr) method, but I think I've ruled this
out. There is nothing stateful in this method, and I've tried dumping
the XML representation of the packageDescr immediately after
populating it; it looks fine to me and is exactly the same whether
compilation succeeds or and fails.
Has anyone done this kind of thing successfully under a heavy load?
Thanks,
Dean.
9:09 a.m.
Is it possible for you to provide a test case capable of reproducing the
problem?
At the same time, I would suggest you to not follow such approach in your
application. Compilation is an extremely heavy process and should not be
done for each request. The ideal approach is to pre-compile (for instance,
we have a contributed ant-task for that) and serialize your rulebase to your
database or filesystem, or at least, compile it only once and cache it at
runtime.
[]s
Edson
2007/7/12, Dean Jones <dean.m.jones(a)gmail.com>:
Hello folks,
I'm experiencing some odd behaviour from Drools (or maybe the Eclipse
compiler) when load-testing my application, and wondered if anyone
else had experienced the same issue. I have a web service which, for
every request, loads in rules from the database, creates a
org.drools.lang.descr.PackageDescr and then uses this to create a
org.drools.rule.Package. The code is something like:
PackageBuilderConfiguration conf = new PackageBuilderConfiguration();
PackageBuilder builder = new PackageBuilder(conf);
PackageDescr packageDescr = new PackageDescr("MyRulebaseName");
populatePackageDescr(packageDescr);
builder.addPackage(packageDescr);
Package _package = builder.getPackage();
return _package;
This code gets run every request. The populatePackageDescr() method
adds imports, globals, functions and rules to the PackageDescr. My
load-test just repeatedly calls the same rulebase, so
populatePackageDescr() will be doing exactly the same thing for each
request. Occasionally (normally once or twice per 100 requests) I get
a rule compilation error (the exact error varies from request to
request) whereas most of the time the same rule compiles fine. This
makes me suspect a thread-safety issue in either the PackageBuilder or
the compiler (I'm using the eclipse compiler).
Initially, I suspected a problem in my
populatePackageDescr(packageDescr) method, but I think I've ruled this
out. There is nothing stateful in this method, and I've tried dumping
the XML representation of the packageDescr immediately after
populating it; it looks fine to me and is exactly the same whether
compilation succeeds or and fails.
Has anyone done this kind of thing successfully under a heavy load?
Thanks,
Dean.
_______________________________________________
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rules-users(a)lists.jboss.org
https://lists.jboss.org/mailman/listinfo/rules-users
--
Edson Tirelli
Software Engineer - JBoss Rules Core Developer
Office: +55 11 3529-6000
Mobile: +55 11 9287-5646
JBoss, a division of Red Hat @ www.jboss.com
10:26 a.m.
Hi Edson,
On 7/12/07, Edson Tirelli <tirelli(a)post.com> wrote:
Is it possible for you to provide a test case capable of reproducing the
problem?
I've written a quick test case, which is attached. When numberOfThreads==1,
everything compiles okay. When numberOfThreads==100, I get function
compilation errors and CompileExceptions from mvel. Clearly there is
nothing shared between these threads as a new test class is created
per thread. If you synchronise the calls to addPackage() and
getPackage() using the class monitor i.e.
synchronized (DroolsLoadTest.class) {
builder.addPackage(packageDescr);
builder.getPackage();
}
then the problems go away. Hope this helps.
At the same time, I would suggest you to not follow such approach
in your
application. Compilation is an extremely heavy process and should not be
done for each request. The ideal approach is to pre-compile (for instance,
we have a contributed ant-task for that) and serialize your rulebase to your
database or filesystem, or at least, compile it only once and cache it at
runtime.
That's very sensible advice. Our situation is slightly different as
users are allowed to change the rules used by a running service, so we
need to reflect any changes when a new request comes in. We are
planning to apply caching if performance is an issue, but we were
trying to assess performance of application under load when this
thread safety issue arose.
Thanks for your help,
Dean.
11:43 a.m.
Dean
Thanks, we will investigate that asap.
[]s
Edson
2007/7/12, Dean Jones <dean.m.jones(a)gmail.com>:
Hi Edson,
On 7/12/07, Edson Tirelli <tirelli(a)post.com> wrote:
>
> Is it possible for you to provide a test case capable of reproducing
the
> problem?
>
I've written a quick test case, which is attached. When
numberOfThreads==1,
everything compiles okay. When numberOfThreads==100, I get function
compilation errors and CompileExceptions from mvel. Clearly there is
nothing shared between these threads as a new test class is created
per thread. If you synchronise the calls to addPackage() and
getPackage() using the class monitor i.e.
synchronized (DroolsLoadTest.class) {
builder.addPackage(packageDescr);
builder.getPackage();
}
then the problems go away. Hope this helps.
> At the same time, I would suggest you to not follow such approach in
your
> application. Compilation is an extremely heavy process and should not be
> done for each request. The ideal approach is to pre-compile (for
instance,
> we have a contributed ant-task for that) and serialize your rulebase to
your
> database or filesystem, or at least, compile it only once and cache it
at
> runtime.
>
That's very sensible advice. Our situation is slightly different as
users are allowed to change the rules used by a running service, so we
need to reflect any changes when a new request comes in. We are
planning to apply caching if performance is an issue, but we were
trying to assess performance of application under load when this
thread safety issue arose.
Thanks for your help,
Dean.
_______________________________________________
rules-users mailing list
rules-users(a)lists.jboss.org
https://lists.jboss.org/mailman/listinfo/rules-users
--
Edson Tirelli
Software Engineer - JBoss Rules Core Developer
Office: +55 11 3529-6000
Mobile: +55 11 9287-5646
JBoss, a division of Red Hat @ www.jboss.com
2:49 p.m.
New subject: how to create local variable
Folks,
I have a rule where I am repeating part of it twice :
($cs.getSuppCode().substring(4, 6)), and I would like to replace it with
variable... how can I do that? The solution with "in" doesn't worl
because it is a java code needed to perform calculations for
variable.....
Please see the rule below:
rule "SupplierView: Headquarter Supplier Code should end on 25 or 30."
when
$cs : SupplierView(corporate == true)
eval($cs.getSuppCode().substring(4, 6) == "25" ||
$cs.getSuppCode().substring(4, 6) == "30")
then
ValidationErrorFacade.getInstance().registerError($cs, new
ValidationError("Headquarter Supplier Code should end on 25 or 30."));
end
Thanks,
-Sergey
**********************
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3:18 p.m.
New subject: how to create local variable
It is not possible to assign the result of an arbitrary method call to a
variable right now. So, your best option is probably to do (please note the
use of inline-eval):
*rule* "SupplierView: Headquarter Supplier Code should end on 25 or 30."
*when*
$cs : SupplierView(corporate == *true,* eval( suppCode.substring(4,
6).equals( "25" ) || suppCode.substring(4, 6).equals( "30" ) ) )
*then*
ValidationErrorFacade.getInstance().registerError($cs,
*new*ValidationError("Headquarter
Supplier Code should end on 25 or 30."));
*end*
A more clean solution is to use "matches" operator. If your rule states
that Supplier Code must END with 25 or 30, you can do:
*rule* "SupplierView: Headquarter Supplier Code should end on 25 or 30."
*when*
$cs : SupplierView(corporate == *true,* suppCode matches ".*25" ||
matches ".*30" )
*then*
ValidationErrorFacade.getInstance().registerError($cs,
*new*ValidationError("Headquarter
Supplier Code should end on 25 or 30."));
*end*
Hope it helps.
[]s
Edson
2007/7/12, Manukyan, Sergey <SManukyan(a)lear.com>:
Folks,
I have a rule where I am repeating part of it twice : ($cs.getSuppCode().substring(4,
6)), and I would like to replace it with variable… how can I do that? The
solution with "in" doesn't worl because it is a java code needed to
perform
calculations for variable…..
Please see the rule below:
* *
*rule* "SupplierView: Headquarter Supplier Code should end on 25 or 30."
*when*
$cs : SupplierView(corporate == *true*)
*eval*($cs.getSuppCode().substring(4, 6) == "25" ||
$cs.getSuppCode().substring(4, 6) == "30")
*then*
ValidationErrorFacade.getInstance().registerError($cs,
*new*ValidationError("Headquarter
Supplier Code should end on 25 or 30."));
*end*
Thanks,
-Sergey
**********************
** LEGAL DISCLAIMER **
**********************
This E-mail message and any attachments may contain
legally privileged, confidential or proprietary
information. If you are not the intended recipient(s),
or the employee or agent responsible for delivery of
this message to the intended recipient(s), you are
hereby notified that any dissemination, distribution
or copying of this E-mail message is strictly
prohibited. If you have received this message in
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--
Edson Tirelli
Software Engineer - JBoss Rules Core Developer
Office: +55 11 3529-6000
Mobile: +55 11 9287-5646
JBoss, a division of Red Hat @ www.jboss.com
3:40 p.m.
New subject: how to create local variable
Thank you Edson,
I liked the solution with matches, it is much cleaner....
-Sergey
________________________________
From: rules-users-bounces(a)lists.jboss.org
[mailto:rules-users-bounces@lists.jboss.org] On Behalf Of Edson Tirelli
Sent: Thursday, July 12, 2007 4:19 PM
To: Rules Users List
Subject: Re: [rules-users] how to create local variable
It is not possible to assign the result of an arbitrary method call
to a variable right now. So, your best option is probably to do (please
note the use of inline-eval):
rule "SupplierView: Headquarter Supplier Code should end on 25 or 30."
when
$cs : SupplierView(corporate == true, eval(
suppCode.substring(4, 6).equals( "25" ) || suppCode.substring(4,
6).equals( "30" ) ) )
then
ValidationErrorFacade.getInstance().registerError($cs, new
ValidationError("Headquarter Supplier Code should end on 25 or 30."));
end
A more clean solution is to use "matches" operator. If your rule
states that Supplier Code must END with 25 or 30, you can do:
rule "SupplierView: Headquarter Supplier Code should end on 25 or 30."
when
$cs : SupplierView(corporate == true, suppCode matches
".*25" || matches ".*30" )
then
ValidationErrorFacade.getInstance().registerError($cs, new
ValidationError("Headquarter Supplier Code should end on 25 or 30."));
end
Hope it helps.
[]s
Edson
2007/7/12, Manukyan, Sergey < SManukyan(a)lear.com>:
Folks,
I have a rule where I am repeating part of it twice :
($cs.getSuppCode().substring(4, 6)), and I would like to replace it with
variable... how can I do that? The solution with "in" doesn't worl
because it is a java code needed to perform calculations for
variable.....
Please see the rule below:
rule "SupplierView: Headquarter Supplier Code should end on 25 or 30."
when
$cs : SupplierView(corporate == true)
eval($cs.getSuppCode().substring(4, 6) == "25" ||
$cs.getSuppCode().substring(4, 6) == "30")
then
ValidationErrorFacade.getInstance().registerError($cs, new
ValidationError("Headquarter Supplier Code should end on 25 or 30."));
end
Thanks,
-Sergey
**********************
** LEGAL DISCLAIMER **
**********************
This E-mail message and any attachments may contain
legally privileged, confidential or proprietary
information. If you are not the intended recipient(s),
or the employee or agent responsible for delivery of
this message to the intended recipient(s), you are
hereby notified that any dissemination, distribution
or copying of this E-mail message is strictly
prohibited. If you have received this message in
error, please immediately notify the sender and
delete this E-mail message from your computer.
_______________________________________________
rules-users mailing list
rules-users(a)lists.jboss.org
https://lists.jboss.org/mailman/listinfo/rules-users
--
Edson Tirelli
Software Engineer - JBoss Rules Core Developer
Office: +55 11 3529-6000
Mobile: +55 11 9287-5646
JBoss, a division of Red Hat @ www.jboss.com
3:11 a.m.
New subject: how to create local variable
Or what about having a rule that creates the substring?
Class SupplierCode {
private String code;
private SupplierView parent;
public SubString(SupplierView parent, String code) {
this.code = code;
this.parent = parent;
}
public String getCode() {
return this.code;
}
public SupplierView getParent() {
return this.parent;
}
}
rule "suppliercode"
when
$sv : SupplierView( $sc : suppCode )
then
insert(new SupplierCode($sv, $sc.substring(4, 6)));
end
rule "main"
when
$sv : SupplierView(corporate == true)
$sc : SupplierCode( code in ('25, '30'), parent == $cs )
then
ValidationErrorFacade.getInstance().registerError($cs, new
ValidationError("Headquarter Supplier Code should end on 25 or 30."));
end
This way you are also making the business rule as to what supplier codes
to accept a Drools rule (and no use of eval!)
(Sorry, a boring day at work and I felt an urge to contribute!)
Mike
________________________________
From: rules-users-bounces(a)lists.jboss.org
[mailto:rules-users-bounces@lists.jboss.org] On Behalf Of Manukyan,
Sergey
Sent: 12 July 2007 21:40
To: Rules Users List
Subject: RE: [rules-users] how to create local variable
Thank you Edson,
I liked the solution with matches, it is much cleaner....
-Sergey
________________________________
From: rules-users-bounces(a)lists.jboss.org
[mailto:rules-users-bounces@lists.jboss.org] On Behalf Of Edson Tirelli
Sent: Thursday, July 12, 2007 4:19 PM
To: Rules Users List
Subject: Re: [rules-users] how to create local variable
It is not possible to assign the result of an arbitrary
method call to a variable right now. So, your best option is probably to
do (please note the use of inline-eval):
rule "SupplierView: Headquarter Supplier Code should end on 25
or 30."
when
$cs : SupplierView(corporate == true, eval(
suppCode.substring(4, 6).equals( "25" ) || suppCode.substring(4,
6).equals( "30" ) ) )
then
ValidationErrorFacade.getInstance().registerError($cs, new
ValidationError("Headquarter Supplier Code should end on 25 or 30."));
end
A more clean solution is to use "matches" operator. If your
rule states that Supplier Code must END with 25 or 30, you can do:
rule "SupplierView: Headquarter Supplier Code should end on 25
or 30."
when
$cs : SupplierView(corporate == true, suppCode
matches ".*25" || matches ".*30" )
then
ValidationErrorFacade.getInstance().registerError($cs, new
ValidationError("Headquarter Supplier Code should end on 25 or 30."));
end
Hope it helps.
[]s
Edson
2007/7/12, Manukyan, Sergey < SManukyan(a)lear.com>:
Folks,
I have a rule where I am repeating part of it twice :
($cs.getSuppCode().substring(4, 6)), and I would like to replace it with
variable... how can I do that? The solution with "in" doesn't worl
because it is a java code needed to perform calculations for
variable.....
Please see the rule below:
rule "SupplierView: Headquarter Supplier Code should end on 25
or 30."
when
$cs : SupplierView(corporate == true)
eval($cs.getSuppCode().substring(4, 6) == "25" ||
$cs.getSuppCode().substring(4, 6) == "30")
then
ValidationErrorFacade.getInstance().registerError($cs, new
ValidationError("Headquarter Supplier Code should end on 25 or 30."));
end
Thanks,
-Sergey
**********************
** LEGAL DISCLAIMER **
**********************
This E-mail message and any attachments may contain
legally privileged, confidential or proprietary
information. If you are not the intended recipient(s),
or the employee or agent responsible for delivery of
this message to the intended recipient(s), you are
hereby notified that any dissemination, distribution
or copying of this E-mail message is strictly
prohibited. If you have received this message in
error, please immediately notify the sender and
delete this E-mail message from your computer.
_______________________________________________
rules-users mailing list
rules-users(a)lists.jboss.org
https://lists.jboss.org/mailman/listinfo/rules-users
--
Edson Tirelli
Software Engineer - JBoss Rules Core Developer
Office: +55 11 3529-6000
Mobile: +55 11 9287-5646
JBoss, a division of Red Hat @ www.jboss.com
7:32 a.m.
I think I've alread fixed this in trunk - when dealing with add/removing
stuff I now do a block syncronisation on the pkgs instance. If that test
is clean, we should add it to the list of integration tests, to track
regressions.
Mark
Edson Tirelli wrote:
Dean
Thanks, we will investigate that asap.
[]s
Edson
2007/7/12, Dean Jones <dean.m.jones(a)gmail.com
<mailto:dean.m.jones@gmail.com>>:
Hi Edson,
On 7/12/07, Edson Tirelli <tirelli(a)post.com
<mailto:tirelli@post.com>> wrote:
>
> Is it possible for you to provide a test case capable of
reproducing the
> problem?
>
I've written a quick test case, which is attached. When
numberOfThreads==1,
everything compiles okay. When numberOfThreads==100, I get function
compilation errors and CompileExceptions from mvel. Clearly there is
nothing shared between these threads as a new test class is created
per thread. If you synchronise the calls to addPackage() and
getPackage() using the class monitor i.e.
synchronized (DroolsLoadTest.class) {
builder.addPackage(packageDescr);
builder.getPackage();
}
then the problems go away. Hope this helps.
> At the same time, I would suggest you to not follow such
approach in your
> application. Compilation is an extremely heavy process and
should not be
> done for each request. The ideal approach is to pre-compile (for
instance,
> we have a contributed ant-task for that) and serialize your
rulebase to your
> database or filesystem, or at least, compile it only once and
cache it at
> runtime.
>
That's very sensible advice. Our situation is slightly different as
users are allowed to change the rules used by a running service,
so we
need to reflect any changes when a new request comes in. We are
planning to apply caching if performance is an issue, but we were
trying to assess performance of application under load when this
thread safety issue arose.
Thanks for your help,
Dean.
_______________________________________________
rules-users mailing list
rules-users(a)lists.jboss.org <mailto:rules-users@lists.jboss.org>
https://lists.jboss.org/mailman/listinfo/rules-users
--
Edson Tirelli
Software Engineer - JBoss Rules Core Developer
Office: +55 11 3529-6000
Mobile: +55 11 9287-5646
JBoss, a division of Red Hat @ www.jboss.com <http://www.jboss.com>
------------------------------------------------------------------------
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rules-users mailing list
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https://lists.jboss.org/mailman/listinfo/rules-users
10:45 a.m.
Hi Mark,
On 7/13/07, Mark Proctor <mproctor(a)codehaus.org> wrote:
I think I've alread fixed this in trunk - when dealing with add/removing
stuff I now do a block syncronisation on the pkgs instance. If that test is
clean, we should add it to the list of integration tests, to track
regressions.
I just tried running my test against a build from the trunk (after
faffing around with maven for a while) and I still get varying numbers
of mvel exceptions and function compilation errors.
Dean.
7:26 a.m.
We are going to need an integration test, to reproduce this, can you
supply one?
Mark
Dean Jones wrote:
Hi Mark,
On 7/13/07, Mark Proctor <mproctor(a)codehaus.org> wrote:
>
> I think I've alread fixed this in trunk - when dealing with
> add/removing
> stuff I now do a block syncronisation on the pkgs instance. If that
> test is
> clean, we should add it to the list of integration tests, to track
> regressions.
>
I just tried running my test against a build from the trunk (after
faffing around with maven for a while) and I still get varying numbers
of mvel exceptions and function compilation errors.
Dean.
_______________________________________________
rules-users mailing list
rules-users(a)lists.jboss.org
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4:48 a.m.
On 7/14/07, Mark Proctor <mproctor(a)codehaus.org> wrote:
We are going to need an integration test, to reproduce this, can you
supply one?
Okay, I've just converted the simple test that I added earlier to a
Junit test. The test is not guaranteed to fail if there are thread
safety errors, just very likely to fail (don't know if this is
acceptable for you). Initially, I wrote a test which guaranteed that
calls to the addPackage() and getPackage() methods were interleaved by
different threads, but, annoyingly, this test passed. It seems that a
context-switch halfway through one of these methods is necessary to
provoke the problem (which is difficult to guarantee :-)
Dean.
6305
days inactive
6347
days old
13 comments
5 participants
participants (5)
-
Anstis, Michael (M.) -
Dean Jones -
Edson Tirelli -
Manukyan, Sergey -
Mark Proctor