RE: Allocate memory

["Boehm, Hans" <hans dot boehm at hp dot com>]

Both the garbage collector and gcj have been used with much larger heaps, though I'm personally not sure how much of that has been done under Windows.

How are you constructing the large strings?  How long are the files?

It would be good to look at the GC log.  One particularly useful piece of information would be the heap size when it's failing.

Hans

> -----Original Message-----
> From: java-owner@gcc.gnu.org [mailto:java-owner@gcc.gnu.org]
> On Behalf Of Dimiter Stamenov
> Sent: Tuesday, February 12, 2008 12:54 PM
> To: java@gcc.gnu.org
> Subject: Re: Allocate memory
>
> So Hans you think that allocating 128 MB is not a problem? Do
> you mean that the compiled application should allocate it
> automatically at runtime?
>
> The gcj version is 4.3 on 32-bit Windows XP. I am reading a
> number of text files and put their contents in a
> HashMap<String, String> (file name, text).
>
> In fact I need the text to be loaded in memory no matter in what way.
>
>
>
>  >-------- Оригинално писмо --------
>  >От:  "Boehm, Hans" <hans.boehm@hp.com>
>  >Относно: RE: Allocate memory
>  >До: Dimiter Stamenov <pamir@abv.bg>, "java@gcc.gnu.org"
> <java@gcc.gnu.org>  >Изпратено на: Вторник, 2008, Февруари 12
> 21:57:46 EET
>  >----------------------------------
>  >
>  >This is a reasonably new version of gcj?  On a 32-bit
> platform?  LinkedList or ArrayList?  Windows?  Linux?
>  >
>  >Certainly allocating 128 MB should not be an issue.
> Allocating a single 128MB contiguous object might be an
> issue, at least if you do it repeatedly on a 32-bit platform.
>  >
>  >You can often get some idea what's going on by defining the
> GC_PRINT_STATS environment variable, and looking at the
> resulting GC log.
>  >
>  >Hans
>  >
>  >> -----Original Message-----
>  >> From: java-owner@gcc.gnu.org
> [mailto:java-owner@gcc.gnu.org]  >> On Behalf Of Dimiter
> Stamenov  >> Sent: Tuesday, February 12, 2008 10:58 AM  >>
> To: java@gcc.gnu.org  >> Subject: Re: Allocate memory  >>  >>
> In fact I know very well why it's running out of memory - I
> >> must fill a large List which consumes the memory.
>  >>
>  >> When I use standard JRE I am starting application with
> >> -Xmx128M argument and it is OK, but with gcj I don't know
> >> what to do...
>  >>
>  >> May be in this case I can not use gcj at all, what do you think?
>  >>
>  >>
>  >>  >-------- Оригинално писмо --------  >>  >От:  Andrew
> Haley <aph@redhat.com>  >>  >Относно: Re: Allocate memory  >>
>  >До: Dimiter Stamenov <pamir@abv.bg>  >>  >Изпратено на:
> Вторник, 2008, Февруари 12 19:52:33 EET  >>
> >----------------------------------
>  >>  >
>  >>  >Dimiter Stamenov wrote:
>  >>  >> OK, but I am getting OutOfMemoryException - so what
> could be done?
>  >>  >
>  >>  >Well, it's either really running out of memory or
> you've hit a bug.
>  >>  >
>  >>  >> Do you mean that I have to rewrite that part of the
> code in C++?
>  >>  >
>  >>  >I wouldn't have thought so.  The stack trace should
> give  >> you an idea why it's  >running out of memory.
>  >>  >
>  >>  >Andrew.
>  >>  >
>  >>  >
>  >>  >>  >Dimiter Stamenov wrote:
>  >>  >>  >> Hi,
>  >>  >>  >>
>  >>  >>  >> Is there any way in gcj compilation to tell the
> >> compiled executable to allocate more memory?
>  >>  >>  >
>  >>  >>  >> I mean something like -Xmx JVM argument when
> running  >> a pure Java application.
>  >>  >>  >
>  >>  >>  >Not that I know of.  It's not something you'd need, anyway:
>  >>  >>  >our gc doesn't allocate memory in a single block as
>  >> Sun's JVM  >>  >does.
>  >>  >
>  >>
>  >
>