[mapserver-dev] Re: Large Shape File Performance

[Paul Ramsey]

All, I have added another patch which addresses scanning the bitmap
status structure more efficiently. Here's the results for the two
patches.

Two performance patches at:
http://trac.osgeo.org/mapserver/ticket/2282

Summary:

Performance patches radically improved the selective case and
left the un-selective case in reasonable shape.

Definitions of tests:

o Indexed: Render 20 features of 1.8M, using an index scan to only
 pull the features needed from the SHP file.  Tests the selective
data access case.
o Unindexed: Render 20 features of 1.8M, using no index. Forces
bounds from every feature to be read.  Tests the un-selective
data access case

Mapserver 5.0

  Indexed: 164ms
  Unindexed: 990ms

Mapserver SVN + SHX Patch

  Indexed: 48ms
  Unindexed: 1015ms

Mapserver SVN + Bitmap Patch

  Indexed: 143ms
  Unindexed: 975ms

Mapserver SVN + Bitmap Patch + SVN Patch

  Indexed: 28ms
  Unindexed: 991ms


On Sat, Apr 19, 2008 at 9:40 AM, Paul Ramsey <pramsey at cleverelephant.ca> wrote:
> All,
>
>  I've done a patch that seems to improve the large shape file
>  performance while not overly affecting the standard performance. I am
>  interested in folks trying it out on their own systems and seeing if
>  the timings are better for them. Also in people who do file
>  creation/writing with mapscript confirming I haven't broken that
>  functionality.
>
>  Patch attached to ticket: http://trac.osgeo.org/mapserver/ticket/2282
>
>  Thanks,
>
>  Paul
>