[GRASS-user] r.sun.daily with multiple CPU cores: error uncompressing raster data ...

[Dylan Beaudette]

On Sat, Dec 30, 2017 at 2:32 PM, Markus Metz
<markus.metz.giswork at gmail.com> wrote:
>
>
> On Fri, Dec 29, 2017 at 5:07 PM, Dylan Beaudette <dylan.beaudette at gmail.com>
> wrote:
>>
>> Hi everyone,
>>
>> First of all, thanks in advance for the r.sun.daily module which is a
>> nice replacement for my amateurish attempts over the last 12 years.
>>
>> I am currently working on an annual beam radiance map for a large
>> geographic region, at 30m res: 70,953 x 46,964 cells. This is far too
>> large for a single pass of r.horizon or r.sun on my machine so I have
>> split the data into 5,000 x 5,000 cell tiles with 100 cells of
>> overlap. This seems to be sufficient for my purposes and the edge
>> effects are tolerable.
>>
>> At 8-15 minutes / tile / day (r.sun) and 54 tiles this job calls for
>> multiple CPU cores. All of the parallel processing that I use is (as
>> far as I know) contained within the same region.
>>
>>
>> I have had good success with running r.horizon in parallel via GNU
>> parallel like this:
>>
>> # 1: start angle
>> # 2: angle step
>> # 3: elevation tile
>> seq 0 $step 330 | parallel --gnu --progress "bash make-hz-maps.sh {}
>> $step $elev"
>>
>> Which is just a wrapper around r.horizon and run in parallel "within"
>> tiles.
>>
>> Next, I run r.sun.daily (8 CPU cores) within tiles:
>>
>> r.sun.daily --overwrite elevation=$elev aspect=$asp slope=$slope \
>> start_day=1 end_day=365 beam_rad=$beam horizon_basename=hzangle
>> horizon_step=$step nprocs=8
>>
>>
>> The r.sun.daily modules finishes without error about 50-60% of the
>> time, results look good. The other 50-40% of the the time I get this:
>>
>>
>> ERROR: Error uncompressing raster data for row 2605 of
>>        <r_sun_crop8255_beam_rad_tmp_352>
>> *** buffer overflow detected ***: g.message terminated
>> ======= Backtrace: =========
>> /lib/x86_64-linux-gnu/libc.so.6(+0x7329f)[0x7f8b9a70129f]
>> /lib/x86_64-linux-gnu/libc.so.6(__fortify_fail+0x5c)[0x7f8b9a79c83c]
>> /lib/x86_64-linux-gnu/libc.so.6(+0x10d710)[0x7f8b9a79b710]
>> /lib/x86_64-linux-gnu/libc.so.6(+0x10cc19)[0x7f8b9a79ac19]
>> /lib/x86_64-linux-gnu/libc.so.6(_IO_default_xsputn+0xbc)[0x7f8b9a70961c]
>> /lib/x86_64-linux-gnu/libc.so.6(_IO_vfprintf+0x1cc5)[0x7f8b9a6d9905]
>> /lib/x86_64-linux-gnu/libc.so.6(__vsprintf_chk+0x84)[0x7f8b9a79aca4]
>>
>> /usr/local/grass-7.5.svn/lib/libgrass_gis.7.5.svn.so(+0x1343c)[0x7f8b9aa6a43c]
>>
>> /usr/local/grass-7.5.svn/lib/libgrass_gis.7.5.svn.so(G_fatal_error+0xbf)[0x7f8b9aa6accf]
>> g.message(main+0x254)[0x400dd4]
>> /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xf5)[0x7f8b9a6aff45]
>> g.message[0x400ea2]
>>
>>
>> I can't seem to replicate the problem, as subsequent runs with the
>> same parameters and in the same tile are successful! This leads me to
>> think that:
>>
>> * some aspect of this approach is not thread safe
>> * there is something wrong with my computer
>> * there is a subtle bug in the raster writing / reading code when
>> invoked in parallel
>>
>>
>> I have encountered similar raster reading errors in the past,
>> typically in the context of parallel processing:
>>
>> https://trac.osgeo.org/grass/ticket/2762
>>
>> https://trac.osgeo.org/grass/ticket/2764
>>
>>
>> http://osgeo-org.1560.x6.nabble.com/Error-reading-raster-data-for-row-xxx-only-when-using-r-series-and-t-rast-series-td5229569i20.html
>>
>> https://lists.osgeo.org/pipermail/grass-dev/2015-July/075691.html
>>
>>
>> Here is some information on my system and version of GRASS:
>>
>>  ./configure  --enable-64bit --with-libs=/usr/lib --without-pthread
>> --without-odbc --without-mysql --with-readline --with-cxx
>> --enable-largefile --with-freetype
>> --with-freetype-includes=/usr/include/freetype2 --with-sqlite
>> --with-python --with-geos=/usr/local/bin/geos-config --without-opencl
>> --with-opencl-includes=/usr/include/CL/ --with-postgres
>> --with-postgres-includes=/usr/include/postgresql/
>> --with-postgres-libs=/usr/lib/
>> --with-proj-share=/usr/local/share/proj/
>>
>> version=7.5.svn
>> date=2017
>> revision=r71964
>> build_date=2017-12-21
>> build_platform=x86_64-pc-linux-gnu
>> build_off_t_size=8
>>
>>
>> Any ideas?
>
> Please try the patch attached to ticket #2764 helps to get closer to the
> problem.
>
> Markus M
>

Hi Markus,

Thank you for the quick reply and patch. I have recompiled with the
patch from #2764 and now waiting to see what happens.

Happy New Year!

Dylan