bug#6237: 23.2; INSUFFICIENT RESOURCES writing file via CIFS

[Jack Holloway]

On 5/21/2010 11:31 PM, Eli Zaretskii wrote:
> > Date: Fri, 21 May 2010 19:12:41 -0700
> > From: Jack Holloway<forum2@sprucehead.com>
> > Cc: 6237@debbugs.gnu.org
> >
> > Saving a 32MB file to a CIFS path fails.  Examining Procmon
> > events shows a return status "INSUFFICIENT RESOURCES" on a WriteFile
> > with length 32MB.
> >
> > Perhaps write-region should break down the write into a series
> > of blksize writes?
> >      
> Can you see which size of a single write succeeds with that volume?
>
> Also, could you see how many bytes did it succeed to write before the
> failure?
>    
I tried successively larger buffers starting at 32KB, viz.
Written 32K
Written 48K
Written 64K
Written 96K
Written 128K
Written 192K
Written 256K
Written 384K
Written 512K
Written 768K
Written 1024K
Written 1536K
Written 2048K
Written 3072K
Written 4096K
Written 6144K
Written 8192K
Written 12288K
Written 16384K
Written 24576K
!!! Unable to append - (error IO error writing 
z:/Temp/test/temp-write-once-032768: Invalid argument)
!!! Unable to append - (error IO error writing 
z:/Temp/test/temp-write-once-049152: Invalid argument)
!!! Unable to append - (error IO error writing 
z:/Temp/test/temp-write-once-065536: Invalid argument)
!!! Unable to append - (error IO error writing 
z:/Temp/test/temp-write-once-098304: Invalid argument)
!!! Unable to append - (error IO error writing 
z:/Temp/test/temp-write-once-131072: Invalid argument)
!!! Unable to append - (error IO error writing 
z:/Temp/test/temp-write-once-196608: Invalid argument)

The would-be 32MB file exists, with zero length.
> > copy-file doesn't have this problem.
> >      
> The MS-Windows version of copy-file doesn't use WriteFile.  It uses
> CopyFile.
>
> Anyway, how did you use copy-file?  Was the source file on the same
> CIFS volume, or was it on a local disk?
>
>    
I've tried all 4 combinations of {internal, CIFS}*{src,dest} with 
transfer sizes up to
196MB without a problem,

I was referring to DEFUN ("copy-file",...) in fileio.c which writes in 
16K blocks,
...
while ((n = emacs_read (ifd, buf, sizeof buf)) > 0)
    if (emacs_write (ofd, buf, n) != n)
      report_file_error ("I/O error", Fcons (newname, Qnil));
...

as opposed to DEFUN ("write-region",...) which, in this case, writes the 
entire buffer
...
else if (XINT (start) != XINT (end))
    {
      failure = 0 > a_write (desc, Qnil,
                 XINT (start), XINT (end) - XINT (start),
&annotations, &coding);
      save_errno = errno;
    }
...

I know nothing about Windows internals, but it would seem that some 
downstream
WinNT I/O routine can't handle 32MB or larger writes, so perhaps 
write-region could segment
the write?  The annotations hair makes it hard for me to see if this is 
easy.

    Jack