[GRASS-dev] [GRASS GIS] #2750: LZ4 when writing raster rows; better than double I/O bound r.mapcalc speed

[GRASS GIS]

#2750: LZ4 when writing raster rows; better than double I/O bound r.mapcalc speed
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  Reporter:  sprice       |      Owner:  grass-dev@…
      Type:  enhancement  |     Status:  new
  Priority:  normal       |  Milestone:  7.2.1
 Component:  Raster       |    Version:  svn-trunk
Resolution:               |   Keywords:  ZLIB LZ4 ZSTD
       CPU:  OSX/Intel    |   Platform:  MacOSX
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Comment (by mmetz):

 Replying to [comment:61 neteler]:
 > Replying to [comment:60 mmetz]:
 > > Notes on NULL file compression could be added to the raster intro.
 >
 > Done in r70669 and r70670.
 >
 > Proposal: I would suggest to make NULL file compression the default in
 trunk.

 Suggested tests:

 * have a raster map with NULL cells without NULL compression

  export GRAS_COMPRESS_NULLS=1

  test the result of r.compress

  test the result of r.null -z

 * have a raster map with NULL cells with NULL compression

  unset GRAS_COMPRESS_NULLS

  test the result of r.compress

  test the result of r.null -z

 * have two raster maps, one with compressed NULL cells, one with
 uncompressed NULL cells

  export GRAS_COMPRESS_NULLS=1

  test the result of mapa + mapb

  unset GRAS_COMPRESS_NULLS

  test the result of mapa + mapb

 * add your tests here

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Ticket URL: <https://trac.osgeo.org/grass/ticket/2750#comment:63>
GRASS GIS <https://grass.osgeo.org>