db-derby-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Myrna van Lunteren (JIRA)" <derby-...@db.apache.org>
Subject [jira] Commented: (DERBY-1614) Test harness overrides heap size settings when starting Network Server
Date Thu, 03 Aug 2006 17:50:15 GMT
    [ http://issues.apache.org/jira/browse/DERBY-1614?page=comments#action_12425580 ] 
Myrna van Lunteren commented on DERBY-1614:

Assuming that things get put in for a reason and people would document (possibly) the reason
I did some historical research.

The first incantation in source control of this harness server code that I could find already
forces a setting of -sm16m -xm32 -noasyncgc for connecting through RmiJdbc to Weblogic Server
- which was supported in version 1.5 of cloudscape.

Code to accept jvmflags was added in in 2001 in cloudscape, and this section looked then much
like how it was contributed to apache. (see:  http://svn.apache.org/viewvc/db/derby/code/trunk/java/testing/org/apache/derbyTesting/functionTests/harness/NetServer.java?revision=57503&view=markup)

The present code, making this optional depending on jvmflags being set or not went in with
revision 160372 for DERBY-121.
(see: http://svn.apache.org/viewvc/db/derby/code/trunk/java/testing/org/apache/derbyTesting/functionTests/harness/NetServer.java?r1=160372&r2=179859)
There is no specific documentation for this part of the change, but I assume the intent was
to just ensure the NetworkServer's heap size settings would get overwritten when set by jvmflags.

I keep going back and forth between A and B. 
I wonder whether the default heap sizes of jdk131 vs. jdk142 vs. jdk15 etc have changed. 
I also wonder if it's possible for certain jvms to have default sizes that differ from machine
to machine (I know they do differ between Windows and Linux, for example).
I worry about causing failures on machines where previously the tests ran fine.

On the other hand, this change has been in for a while, so maybe it's not affected anyone.
And also, the setting is hidden from view. And not working properly. And to get it working
properly would take more effort, and we should also make sure it can't get overwritten by
settings coming through on testSpecialProps or testJavaFlags. It would be clearer to leave
the setting to the test and remove it from NetServer.java...

So, I cautiously vote for A. 

> Test harness overrides heap size settings when starting Network Server
> ----------------------------------------------------------------------
>                 Key: DERBY-1614
>                 URL: http://issues.apache.org/jira/browse/DERBY-1614
>             Project: Derby
>          Issue Type: Bug
>          Components: Test
>    Affects Versions:
>         Environment: Test frameworks DerbyNet and DerbyNetClient
>            Reporter: John H. Embretsen
>         Assigned To: John H. Embretsen
>             Fix For:
>         Attachments: DERBY-1614_v1.diff, DERBY-1614_v2.diff
> Test specific heap size settings can be passed to the test harness using the jvmflags
system property, for example in a <testname>_app.properties file or at the command line
when starting a test, e.g "-Djvmflags=-Xms32m^-Xmx32m".
> The test harness almost always overrides such settings when starting a new Network Server
using the org.apache.derbyTesting.functionTests.harness.NetServer class of the test harness.
Currently, if _either_ -ms _or_ -Xms is missing from the jvmflags, NetServer.start() adds
-ms16777216. Also, if _either_ -mx _or_ -Xmx is missing from the jvmflags, NetServer.start()
adds -ms33554432. This has been the case since SVN revision 420048 (July 8, 2006).
> Earlier revisions did not override the heap settings unless the newer -Xms or -Xmx flags
were used instead of the -ms and -mx flags. A patch for DERBY-1091 attempted (among other
things) to make the harness recognize the newer flags as well as the older flags, but the
resulting behavior is (most likely) not as intended. 
> If a test is run in either the DerbyNet framework or the DerbyNetClient framework, the
test-specific JVM flags should (probably) be used for the Network Server JVM as well as the
test JVM. Currently, even if non-default heap size flags are passed to the harness, the server
JVM will ignore these settings since the harness adds -ms and/or -mx flags _after_ all other
heap flags. The exception is if both new and old versions of heap flags are passed to the
harness, e.g:
> jvmflags=-ms32m^-Xms32m^-mx128m^-Xmx128m
> Here is the code causing this behaviour:
> if (setJvmFlags && ((jvmflags.indexOf("-ms") == -1) || (jvmflags.indexOf("-Xms")
== -1)))
>      // only setMs if no starting memory was given
>      jvm.setMs(16*1024*1024); // -ms16m
> if (setJvmFlags && ((jvmflags.indexOf("-mx") == -1) || (jvmflags.indexOf("-Xmx")
== -1)))
>      // only setMx if no max memory was given
>      jvm.setMx(32*1024*1024); // -mx32m

This message is automatically generated by JIRA.
If you think it was sent incorrectly contact one of the administrators: http://issues.apache.org/jira/secure/Administrators.jspa
For more information on JIRA, see: http://www.atlassian.com/software/jira


View raw message