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From "E.R. van Es" <e...@cdls.nl>
Subject Re: stress application
Date Thu, 27 Oct 2005 13:47:28 GMT
Hmm didn't test that, but it ran out of memory using 512Mb, it runs fine with 800Mb...  I admit
there might be a memory problem, as there are over 450000 (!) data objects in memory but I
don't want the application to do disc reads for every data fetch (as it runs over data fetching
methods over 10000 times).

On Thu, 27 Oct 2005 14:14:23 +0100
Andrew Mason <andrew@assertis.co.uk> wrote:

> It could just be that it actually DOES need more memory. Out of curiosity at 
> what amount of memory does it stop being a problem ?
> 
> 
> On Thu October 27 2005 2:09 pm, E.R. van Es wrote:
> > Hi,
> >
> >   I gave the program 800Mb of memory, enabled caching and using a
> > BufferedWriter, and the program runs with no noticable slow-down at all. 
> > Maybe I'll stress-test with twice the amount of information for fun :)  Is
> > it possible to do something like "memory leak detection" using some kind of
> > debugging on java programs?
> >
> > Greets,
> > Eric
> >
> > On Thu, 27 Oct 2005 09:26:00 +0200
> >
> > "E.R. van Es" <eric@cdls.nl> wrote:
> > > The data is read from a plain text file and put in simple 'data' objects
> > > first.  I need all data from the file to be available before processing
> > > the templates, so all data objects are saved in an ArrayList, the
> > > getData() method search through the data objects ArrayList for the key
> > > matching and returns only those data objects needed in a new ArrayList.
> > >
> > > Greetings,
> > > Eric
> > >
> > > On Thu, 27 Oct 2005 08:09:57 +0100
> > >
> > > Andrew Mason <andrew@assertis.co.uk> wrote:
> > > > Just out of curiosity where is it gettng the data from ? database ? If
> > > > so are you using a connection pool?
> > > >
> > > > private
> > > >
> > > > On Thu October 27 2005 8:03 am, E.R. van Es wrote:
> > > > > Hi,
> > > > >
> > > > > I'm running a test now with the BufferedWriter, we'll see what
> > > > > happens. About the getData() method, maybe this actually is the leak,
> > > > > it does this:
> > > > >
> > > > > *** CODE ***
> > > > > private ArrayList getData(String key) {
> > > > > 	ArrayList temp = new ArrayList();
> > > > > 	... fetch data here and fill temp ...
> > > > > 	return temp;
> > > > > }
> > > > > *** CODE END ***
> > > > >
> > > > > I'm not a complete java guru, but is there a new temp ArrayList
> > > > > allocated in memory every time I call this method?  won't previous
> > > > > created temp ArrayLists be collected by the garbage collector?
> > > > >
> > > > >
> > > > > Greetings,
> > > > > Eric
> > > > >
> > > > > On Wed, 26 Oct 2005 11:57:08 -0400
> > > > >
> > > > > James Kebinger <jkebinger@gmail.com> wrote:
> > > > > > I would just turn up the amount of memory java can use.
> > > > > > Does point to a possible memory leak somewhere though. What
does
> > > > > > getData() do? Note you're also shadowing the data variable in
> > > > > > processData().
> > > > > >
> > > > > > On 10/26/05, E.R. van Es <eric@cdls.nl> wrote:
> > > > > > > Hi Andrew,
> > > > > > >
> > > > > > > does this really make a memory difference? The generated
files
> > > > > > > themselves are not that big (up to 50kb each) and the writer
is
> > > > > > > closed after each file... I didn't thought about it so
I'll try
> > > > > > > of course :)
> > > > > > >
> > > > > > > Greetings,
> > > > > > > Eric
> > > > > > >
> > > > > > > On Wed, 26 Oct 2005 16:12:28 +0100
> > > > > > >
> > > > > > > Andrew Mason <andrew@assertis.co.uk> wrote:
> > > > > > > > Have you thought about using a buffered writer ?
> > > > > > > >
> > > > > > > > On Wed October 26 2005 4:08 pm, E.R. van Es wrote:
> > > > > > > > > Hello Velocity List,
> > > > > > > > >
> > > > > > > > > i have to create some big monthly reports on
CD. I use a
> > > > > > > > > simple java program to generate all reports in
HTML files
> > > > > > > > > using velocity
> > > > > > >
> > > > > > > templates.
> > > > > > >
> > > > > > > > > All data is pre-loaded and then the reports are
created by
> > > > > > > > > iterating
> > > > > > >
> > > > > > > over
> > > > > > >
> > > > > > > > > the data. However, there are too many files to
create (over
> > > > > > > > > 9600) and after file 7850 I get a java memory
exception. I
> > > > > > > > > use a scheme like
> > > > > > >
> > > > > > > this:
> > > > > > > > > *** JAVA CODE ***
> > > > > > > > > private Context context;
> > > > > > > > >
> > > > > > > > > private void processData() {
> > > > > > > > > ArrayList data = getDataKeys(); // this returns
an array with
> > > > > > > > > all
> > > > > > >
> > > > > > > "data
> > > > > > >
> > > > > > > > > keys" Iterator i = data.iterator();
> > > > > > > > > while (i.hasNext()) {
> > > > > > > > > String key = (String) i.next();
> > > > > > > > > ArrayList data = getData(key); // get all data
objects for
> > > > > > > > > this key. context.put("key", key);
> > > > > > > > > context.put("data", data);
> > > > > > > > > processTemplate("template.vm", key + ".html");
> > > > > > > > > }
> > > > > > > > > }
> > > > > > > > >
> > > > > > > > > private void processTemplate(String template,
String
> > > > > > > > > outputFile) { FileWriter outputFileWriter = new
> > > > > > > > > FileWriter(new File(outputFile));
> > > > > > > > >
> > > > > > > > > Template x = Velocity.getTemplate(template);
> > > > > > > > > x.merge(context, outputFileWriter);
> > > > > > > > >
> > > > > > > > > outputFileWriter.close();
> > > > > > > > > }
> > > > > > > > > *** JAVA CODE END ***
> > > > > > > > >
> > > > > > > > > *** TEMPLATE CODE ***
> > > > > > > > > <html>
> > > > > > > > > ... bla bla ...
> > > > > > > > > #foreach ( $el in $data )
> > > > > > > > > $data.getX()<br>
> > > > > > > > > $data.getY()<br>
> > > > > > > > > and so on and so forth...
> > > > > > > > > #end
> > > > > > > > > ... bla bla ...
> > > > > > > > > </html>
> > > > > > > > > *** TEMPLATE CODE END ***
> > > > > > > > >
> > > > > > > > > As you can see I put every data class in the
context with
> > > > > > > > > identifier "data", my thought was to overwrite
the previous
> > > > > > > > > one and NOT get a
> > > > > > >
> > > > > > > memory
> > > > > > >
> > > > > > > > > problem, however I do get the memory problem.
I can adjust
> > > > > > > > > the java
> > > > > > >
> > > > > > > memory
> > > > > > >
> > > > > > > > > allocation to 1Gb but I was wondering if my approach
just
> > > > > > > > > isn't
> > > > > > >
> > > > > > > correct?
> > > > > > >
> > > > > > > > > I'm not sure about the processTemplate method,
though it
> > > > > > > > > workes
> > > > > > >
> > > > > > > perfectly
> > > > > > >
> > > > > > > > > for the first 7800 files :) By the way: I'm using
> > > > > > > > > velocity-1.4.
> > > > > > > > >
> > > > > > > > > Thanks in advance,
> > > > > > > > > Eric
> > > > > > > > >
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