[postgis-tickets] [PostGIS] #4372: PROJ 6: 4x slowdown on indexes over ST_Transform

[PostGIS]

#4372: PROJ 6: 4x slowdown on indexes over ST_Transform
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  Reporter:  Algunenano  |      Owner:  Algunenano
      Type:  defect      |     Status:  assigned
  Priority:  high        |  Milestone:  PostGIS 3.0.0
 Component:  postgis     |    Version:  trunk
Resolution:              |   Keywords:
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Comment (by Algunenano):

 I have a WIP in https://github.com/postgis/postgis/pull/422 to address
 some of the issues found here.

 The main fix to gain the performance back is to also cache the
 proj_crs_is_swapped calls to avoid making them in every ST_Transform call.

 I'm still investigating further to try to understand why removing the
 invalid set_searchpath makes some calls 10x slower with PROJ6. Also I need
 to review that I haven't broken anything in proj5 ^^

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Ticket URL: <https://trac.osgeo.org/postgis/ticket/4372#comment:8>
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