Re: RE: More than 2GB heap with 64 bit JVM? -- JAVA400-L

I had high hopes for this. I did the ADDENVVAR ENVVAR
(QIBM_RPG_JAVA_PROPERTIES) VALUE('-Xmx4096m), but anytime the JVM starts
up, it complains that -X is unrecognized. Still trying to find some kind
of example.

From: "Gan Zhang" <zhanggan@xxxxxxxxxx>
To: java400-l@xxxxxxxxxxxx
Cc: java400-l@xxxxxxxxxxxx
Date: 06/01/2016 11:48 AM
Subject: Re: RE: More than 2GB heap with 64 bit JVM?
Sent by: "JAVA400-L" <java400-l-bounces@xxxxxxxxxxxx>

[1]
http://www.ibm.com/support/knowledgecenter/ssw_ibm_i_73/rzasc/contrhowjvm.htm

This could help you to setup the heap of JVM called from RPG.

Best regards.

____________________________________________________________________________________________

Gavin, Zhang Gan --

https://w3-connections.ibm.com/profiles/html/profileView.do?key=d77158d7-c5cd-4e6e-a90d-23dddc9cbaba&lang=en

IBM i J9 Team Lead,
Email: zhanggan@xxxxxxxxxx
Phone: +86-10-82452719
Address: 1/F, 28, ZhongGuanCun Software Park, No.8 Dong Bei Wang West
Road, Haidian District, Beijing P.R.China 100193
J9 on i: http://www.ibm.com/developerworks/ibmi/techupdates/java

----- Original message -----
From: Darren Strong <darren@xxxxxxxxx>
Sent by: "JAVA400-L" <java400-l-bounces@xxxxxxxxxxxx>
To: Java Programming on and around the IBM i <java400-l@xxxxxxxxxxxx>
Cc:
Subject: RE: More than 2GB heap with 64 bit JVM?
Date: Wed, Jun 1, 2016 10:01 PM

We use SXSSF method whenever we can. In this case, we're pulling in a
template spreadsheet, so I couldn't find a good way to use SXSSF. I'm
also
not using the "java" command, so extentions like -XMX3G are a bit
foreign
to me. I'm implementing the JVM through RPG.

From: Mitch Gallman <mgallman@xxxxxxxxxxxx>
To: Java Programming on and around the IBM i
<java400-l@xxxxxxxxxxxx>
Date: 06/01/2016 09:51 AM
Subject: RE: More than 2GB heap with 64 bit JVM?
Sent by: "JAVA400-L" <java400-l-bounces@xxxxxxxxxxxx>

If possible rather than increasing the heap you might want to change
your
process to use the Streaming spreadsheet (SXSSF) functionality that
POI
provides. This will allow you to build much bigger spreadsheets
without
consuming so much memory.

[2]https://poi.apache.org/spreadsheet/how-to.html#sxssf

If you still want to increase the max heap it would be done using the
-Xmx
parameter (e.g. Java -Xmx3g Hello)...when I specify -Xmx4g on Java 1.6
I
get an error that the value is too large.

Mitch

-----Original Message-----
From: JAVA400-L [[3]mailto:java400-l-bounces@xxxxxxxxxxxx] On Behalf
Of
Darren
Strong
Sent: Wednesday, June 01, 2016 8:27 AM
To: java400-l@xxxxxxxxxxxx
Subject: More than 2GB heap with 64 bit JVM?

I have a certain application running using the JNI (more specifically,
RPG
calling Java Excel POI HSSF) to create a really large spreadsheet, and
its
running out of memory/heap. We're running a 64bit JVM. If I can
figure
out how to specify a larger maximum heap size, can I go beyond the
current
2GB limit? Is there a way to alter the maximum heap size for a job?
If
not by job, by default?

--
This is the Java Programming on and around the IBM i (JAVA400-L)
mailing
list To post a message email: JAVA400-L@xxxxxxxxxxxx To subscribe,
unsubscribe, or change list options,
visit: [4]http://lists.midrange.com/mailman/listinfo/java400-l
or email: JAVA400-L-request@xxxxxxxxxxxx Before posting, please take a
moment to review the archives at
[5]http://archive.midrange.com/java400-l.

--
This is the Java Programming on and around the IBM i (JAVA400-L)
mailing
list
To post a message email: JAVA400-L@xxxxxxxxxxxx
To subscribe, unsubscribe, or change list options,
visit: [6]http://lists.midrange.com/mailman/listinfo/java400-l
or email: JAVA400-L-request@xxxxxxxxxxxx
Before posting, please take a moment to review the archives
at [7]http://archive.midrange.com/java400-l.

--
This is the Java Programming on and around the IBM i (JAVA400-L)
mailing
list
To post a message email: JAVA400-L@xxxxxxxxxxxx
To subscribe, unsubscribe, or change list options,
visit: [8]http://lists.midrange.com/mailman/listinfo/java400-l
or email: JAVA400-L-request@xxxxxxxxxxxx
Before posting, please take a moment to review the archives
at [9]http://archive.midrange.com/java400-l.

References

Visible links
1.
http://www.ibm.com/support/knowledgecenter/ssw_ibm_i_73/rzasc/contrhowjvm.htm

2. https://poi.apache.org/spreadsheet/how-to.html#sxssf
3. mailto:java400-l-bounces@xxxxxxxxxxxx
4. http://lists.midrange.com/mailman/listinfo/java400-l
5. http://archive.midrange.com/java400-l
6. http://lists.midrange.com/mailman/listinfo/java400-l
7. http://archive.midrange.com/java400-l
8. http://lists.midrange.com/mailman/listinfo/java400-l
9. http://archive.midrange.com/java400-l
--
This is the Java Programming on and around the IBM i (JAVA400-L) mailing
list
To post a message email: JAVA400-L@xxxxxxxxxxxx
To subscribe, unsubscribe, or change list options,
visit: http://lists.midrange.com/mailman/listinfo/java400-l
or email: JAVA400-L-request@xxxxxxxxxxxx
Before posting, please take a moment to review the archives
at http://archive.midrange.com/java400-l.