[Vm-dev] Cog issue? Re: [Pharo-project] StandardFileStream size limit?

[David T. Lewis]

On Thu, Jun 14, 2012 at 11:17:40AM +0200, Bert Freudenberg wrote:
> 
> 
> On 2012-06-14, at 00:09, David T. Lewis wrote:
> 
> > 
> > On Wed, Jun 13, 2012 at 03:00:29PM -0700, Eliot Miranda wrote:
> >> 
> >> On Wed, Jun 13, 2012 at 7:40 AM, David T. Lewis <lewis at mail.msen.com> wrote:
> >> 
> >>> 
> >>> On Wed, Jun 13, 2012 at 04:08:14PM +0200, G?ran Krampe wrote:
> >>>> 
> >>>> Hey!
> >>>> 
> >>>> Ok, so the plot thickens:
> >>>> 
> >>>> If I run this in a "oneclick 1.4" I will get a file write error on 2Gb:
> >>>> 
> >>>> | f b |
> >>>> f := StandardFileStream newFileNamed: 'test'.
> >>>> b := ByteArray new: 1024*1024*100. "100Mb"
> >>>> [30 timesRepeat: [f nextPutAll: b]] ensure: [f close] "3Gb"
> >>>> 
> >>>> 
> >>>> ...but it worked fine using a self built "standard" VM from squeakvm.org
> >>>> (4.4.7.2357)! Same image btw.
> >>>> 
> >>>> Now, does it work with the bleeding edge Cog? Tried r2556 and nope, same
> >>>> problem.
> >>>> 
> >>>> So I "guess" it is a Cog thing? I haven't tried building Cog from source.
> >>>> 
> >>>> regards, G?ran
> >>> 
> >>> Background on large file support, see especially Bert's summary:
> >>> 
> >>> 
> >>> http://forum.world.st/Re-squeak-dev-filesize-reporting-0-for-very-large-files-td4483646.html
> >>> http://bugs.squeak.org/view.php?id=7522
> >>> http://www.suse.de/~aj/linux_lfs.html
> >>> 
> >>> I'm not sure if the Cog VMs are being compiled with the the LFS option,
> >>> although
> >>> I expect that if you compile it yourself with the build options that Bert
> >>> explains,
> >>> then it should start working.
> >>> 
> >> 
> >> I just committed the necessary changes for my branch.  Will rebuild soon.
> >> G?ran, if you're in a hurry build your own?  You'd need to be in
> >> http://www.squeakvm.org/svn/squeak/branches/Cog/unixbuild/bld and run ./mvm.
> >> -- 
> >> best,
> >> Eliot
> > 
> > Excellent :)
> > 
> > Dave
> 
> I wonder why the interpreter VM works though - I didn't see any of those flags in its build settings. Or maybe some Linuxes enable large files by default?
> 
> - Bert -
>

You are right, those flags are not in the build settings.

I just double checked, and it turns out that it is not true that the standard
interpreter VM works. The interpreter VM works for large files when compiled as
a 64-bit executable, and it works when compiled as a 32-bit executable your
instructions for the LFS flags are followed. But the officially distributed
32-bit interpreter VM does not have LFS support enabled, and if you open a file
list on very large file, the file size will not be displayed correctly.

Dave