[GRASS-dev] [GRASS GIS] #1421: scalability of r.terraflow

[GRASS GIS]

#1421: scalability of r.terraflow
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 Reporter:  dnewcomb                  |       Owner:  grass-dev@…              
     Type:  enhancement               |      Status:  new                      
 Priority:  normal                    |   Milestone:  7.0.0                    
Component:  Raster                    |     Version:  svn-develbranch6         
 Keywords:  r.terraflow, large grids  |    Platform:  Linux                    
      Cpu:  x86-64                    |  
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Old description:

> I have an fcell grid of elevations for the state of North Carolina (51000
> rows 133000 columns 6783000000 cells) .  I tried to run r.terraflow in
> GRASS7 ( 8/8/2011 svn snapshot) and ran into the dimension limits.  So I
> patched them according to Glynn's email , http://www.osgeo.org/pipermail
> /grass-user/2004-February/024722.html  and tried again ( Would it be
> better to change the  dimension variable to int instead of  short int?) .
>
> This time my Streams file builds to about 26 GB and then r.terraflow
> bombs with :
>
> MFD flow direction
> D8CUT=999999986991104.000000
> Memory size: 808.00M (847249408) bytes
> Memory manager registering memory in MM_IGNORE_MEMORY_EXCEEDED mode.
> r.terraflow: grass2str.h:145: AMI_STREAM<T>*
> cell2stream(char*, elevation_type, long int*) [with T =
> float, elevation_type = float]: Assertion `nrows * ncols ==
> str->stream_len()' failed.
>
> The memory size is interesting, because I'm giving it 8GB of RAM out of
> 16 GB in the command.  The temp directory has about 900GB of space, so it
> has plenty of room .
>
> The box is 64 bit Ubuntu 11.04
>
> related to ?
>
> http://trac.osgeo.org/grass/ticket/1006

New description:

 I have an fcell grid of elevations for the state of North Carolina (51000
 rows 133000 columns 6783000000 cells) .  I tried to run r.terraflow in
 GRASS7 ( 8/8/2011 svn snapshot) and ran into the dimension limits.  So I
 patched them according to Glynn's email , http://www.osgeo.org/pipermail
 /grass-user/2004-February/024722.html  and tried again ( Would it be
 better to change the  dimension variable to int instead of  short int?) .

 This time my Streams file builds to about 26 GB and then r.terraflow bombs
 with :
 {{{
 MFD flow direction
 D8CUT=999999986991104.000000
 Memory size: 808.00M (847249408) bytes
 Memory manager registering memory in MM_IGNORE_MEMORY_EXCEEDED mode.
 r.terraflow: grass2str.h:145: AMI_STREAM<T>*
 cell2stream(char*, elevation_type, long int*) [with T =
 float, elevation_type = float]: Assertion `nrows * ncols ==
 str->stream_len()' failed.
 }}}
 The memory size is interesting, because I'm giving it 8GB of RAM out of 16
 GB in the command.  The temp directory has about 900GB of space, so it has
 plenty of room .

 The box is 64 bit Ubuntu 11.04

 related to ?

 http://trac.osgeo.org/grass/ticket/1006

--

Comment(by hamish):

 add '!{{{' and '}}}' around code block.

-- 
Ticket URL: <https://trac.osgeo.org/grass/ticket/1421#comment:6>
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