Mailing-List: contact poi-user-help@jakarta.apache.org; run by ezmlm
From: "Christoph Jaeger" <christoph.jaeger@dhl.com>
To: <poi-user@jakarta.apache.org>
Subject: Out of memory errors
Date: Wed, 14 May 2003 15:09:04 +0200
Message-ID: <002501c31a19$ff34c9a0$b71e2b02@at.danzas.com>
MIME-Version: 1.0
Content-Type: text/plain;
	charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
Importance: Normal

Hi,

I am trying to write Excel-files using POIs HSSF classes. This works
quite nicely for small files. But I can not write big files. Somewhere
around 20000 rows with 10 columns is the biggest file I can produce (and
my JVM uses over 70MB of memory when doing so).

I do not use any advanced features. I just create rows with cells
(between 30 and 40 columns) filled with numbers, formatted date, and
short text. No formulas, no fancy formatting (only the fields in the
first row are bold), no borders, no reading of existing files, nothing
special.

I do not want to increase the memory size usable for my JVM, as I create
these Excel files from a web-application and I do not feel too
comfortable changing the startup parameters for my whole Tomcat
installation.

Are there any hints you can give me to decrease memory consumption? I
tried versions 1.5 and 1.10, both seemed to consume the same amount of
memory.

Should I try out the development series (as I do only simple stuff I
hope the features I need are already stable there), or is this known to
use even more memory? I read something in the development mailing list
about a performance branch, which should be easier on memory, may this
be a solution for me, or is not yet stable enough for simple use?

Thanks

Best Regards,

Christoph J=E4ger