Performance concerns how effectively a computing system uses resources.

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47 views

How can I speed up a slow ArcGIS Server 10.2 - PostgreSQL (9.2) ST_Intersects query?

I am troubleshooting a slow st_geometry query in Postgres 9.2 that uses ST_Intersects--a basic Select from table where ST_Intersects type query. table_extent ...
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0answers
21 views

Mapnik performance - large polyline dataset

I'm working with a very large set of polylines - contour data - to be rendered with Mapnik. (The contours are generated using gdal_contour from SRTM data.) At present I'm storing them in PostGIS and ...
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1answer
44 views

Display more than 1000 lines on web map

I've a scenario that I need to display many lines on the map (for instance all road links of Manchester in UK). I am using Leaflet as map plugin. I use geoJSON as source of data, when I try to load ...
2
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0answers
56 views

Performance difference between focal statistics (ArcGIS) and neighbor (GRAS or QGIS)

I tested minimum, maximum, and average neighbor (circle radius = 161 pixel) using ArcGIS, GRASS and QGIS: ArcGIS (10.1): it takes only one minute GRASS (6.4.3): it takes 123 minutes for every output ...
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1answer
62 views

PostGIS: Strategy for fastest select by BBox with an ORDER BY polygon area clause. Cluster?

Update 2 (below) suggests 14% of the table geometries are stored out-of-line with the rest of the table records. This may be a useful clue. The Problem: We've got a table with appx 170,000 WGS84 ...
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1answer
41 views

How to reduce Overpass way QL statement output to just tags?

I am new to Overpass API. Ran this query [way(around:10.0,37.559391,-122.301529);out;] in overpass-turbo.eu and getting lot of information about nodes. I just need to know whether it is valid way or ...
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1answer
29 views

ogr2ogr Spatialite to csv very slow

I am using ogr2ogr to extract point data from a Spatialite db to a csv file:- ogr2ogr -f "CSV" commandtmp.csv dtm2.sqlite -lco GEOMETRY=AS_XYZ -progress -explodecollections the Spatialite db is 7GB ...
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53 views

Spatial query by ESRI ST_Geometry take too long

I am using ESRI ST_Geometry in my application, and I found that the spatial query is rather slow: The following sql is used for query pois inside a certain bounding_box: select * from ( select ...
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0answers
15 views

Showing large number of polygons in SpatiaLite on Android map?

I have 2,300 complex multipolygon features in an offline SpatiaLite database. How can I show them on an Android map without slowing the map to a halt?
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1answer
271 views

How to improve ArcGIS Desktop 10.2.2 and Postgres 9.2 PostGIS geometry performance?

I'm experiencing sever performance issues on a polygon featureclass(PG_GEOMETRY) in a PostgreSQL 9.2 database from a 10.2.2 client. Even when zoomed to an area with 10-20 features within the extent. ...
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1answer
41 views

SQL query within Select tool in ArcGIS model going very slow

I have been working on finding the shortest routes from a series of residential blocks (a shapefile with polygon centroids) to a a number of recreational areas. I have a total of 9 resulting OD cost ...
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1answer
13 views

Avoid sending CSS with each search in CartoDB

We’re developing a project with CartoDB and we want to show each element with a custom image. We are doing this setting the sublayer.setCartoCSS() with something like this: cartocss: "#map { (…) } ...
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1answer
80 views

GeoTIFFS on Geoserver are served slowly, at too low resolution

I have a bunch of large, high resolution GeoTIFFs, that I am serving using GeoServer. I also have a prototype client I wrote using Leaflet. The resolution of the TIFFs is quite high, but despite that ...
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0answers
24 views

QGIS extremely slow to clip vrt on Mac

I've been using QGIS 2.6 (Brighton) happily for awhile but suddenly it became extremely slow during certain operations, after being reasonably fast in past use. I'm merging NAIP JP2 files to virtual ...
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0answers
23 views

Performance problem WMS layers arcgis Server

I am learning to work with ArcGIS for server and with Javascript, HTML5 and CSS3. I have GIS knowledge but this technical part is new to me. I have published WMS layers to my ArcGIS server and can ...
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0answers
21 views

Multibuffer in arcpy is too slow?

I have to make multibuffer to a several shp's (30 or +) and with this code the it takes 30 minutes or more. import arcpy,time,glob,os def multibuffer (probe,Zona_trab,nombarch3,recortes2): ...
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2answers
81 views

Python Script tools for ArcGIS 10.2 is very slow (get raster properties)

I am using python script tools for ArcGIS 10.2, under Windows 8.1 64bit. When I am using the arcpy.GetRasterProperties_management() command, it's very slow to process the data. For example. I tried ...
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1answer
114 views

Chrome/Firefox Performance Issues

Just curious if anyone else is having performance issues with Chrome and Firefox while using an arcgis javascript web application. I have been developing an application that works great in Internet ...
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2answers
202 views

PostGIS ST_Union Performance

I'm trying to execute a 'dissolve' operation in PostGIS using the ST_Union command. The input layer is admittedly quite large and complex. By 'large' I mean 57,771 features, with number of vertices ...
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1answer
52 views

Connecting to ArcSDE with arcpy is slow (ArcSDESQLExecute)

I'm creating an API which will allow queries to be performed on my GeoDatabase. I'm using ArcSDESQLExecute to connect to ArcSDE (backed with an Oracle database). Creating the connection object is very ...
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0answers
111 views

Why is QGIS so much faster on Windows than Mac? (or: Why is QGis so slow on macs?) [closed]

I just went from temporarily using a Windows 7 machine with 4GB of RAM and no video card as far as I know. I'm now using a mac with 16GB of ram, etc. Its a much more powerful machine. However, QGis's ...
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0answers
55 views

Fastest method to join a lot of tables

i have a lot of feature class (see figure 1) the objective is to create one feature class that combines the attribute table (especially one field) of each feature class the attribute table of each ...
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0answers
34 views

How can I prevent ogr2ogr from trying to get the SRID from PostGIS?

I'm running ogr2ogr for a PostGIS to GeoJSON export like this: ogr2ogr -s_srs EPSG:4326 -f GeoJSON unique_geoms.json "PG:host=localhost dbname=local_data user=local_user password=local_pass" -sql ...
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3answers
225 views

Executing Python code takes a lot of time (more than 2 hours)? (Arcgis10.1)

I am executing this Python code, in which I am trying to determinate the position of neighbor parcel (north, south, east, west). It works fine but it took 2 hours for just 50 parcels! I think that ...
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1answer
82 views

GeoServer rendering performance significantly affected by vector icon size

I'm having the craziest GeoServer experience right now and I was hoping to get some input on what might be causing this behaviour. I'm using Apache Bench to benchmark rendering performance for a ...
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0answers
42 views

Any way to speed up my postgis topology creation?

I need to do topology aware simplification, and I'm investigating PostGIS's new topology extension. However it's taking a very long time to create the topology, and I'd like to know if there's ...
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1answer
41 views

Index to speed up ST_HausdorffDistance?

When comparing similarity of linestrings with ST_HausdorffDistance (or another type of similarity function), is there a way to use an index to speed up the search for similar linestrings?
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1answer
21 views

Does mixing geometries of different granularity affect POSTGIS index efficiency?

My POSTGIS table contains a lot of small non-overlapping geometries and I do mostly bbox queries. I would like to add larger / coarser grained geometries to the database (counties, provinces, country) ...
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0answers
16 views

Long delay when updating rows of a feature layer or modifying elements of a graphic layer using arcObjects in java

We are developing a simple AddIn for arcMap for the first time using arcObjects in java. The application consists basically on the following steps: 1. Obtain a Network layer which was loaded in ...
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2answers
184 views

How to improve the performance of an OpenLayers based API containing a large number of layers?

I have a GIS SDK with WMS layers and Vector layers (with information from Geoserver). I have methods for setting a style map, but I have a performance problem. When I set same style for 30 layers, ...
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1answer
114 views

Will a tile cache serving PNG tiles be slower than JPEG?

I'm trying to figure out the best format to serve my tiles. I'm creating an ESRI tile cache. It will be consumed internally through ArcMap from our server, not online. There are a lot of different ...
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1answer
64 views

slow Python script pulling from an iSeries database

I've converted and updated some python scripts that exported data from an iSeries database (HTE) to Access to export the same data to a fgdb. My biggest issue is the time it's taking to export the ...
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2answers
120 views

Maximizing Code Performance for Shapely

I've written this code in order to calculate the percent cover of grassland within a national park, within 20km^2 of points of recorded occurrences for a species. It is designed to only consider the ...
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0answers
109 views

Mosaic many rasters in ArcGIS is slow

I am trying to merge 166 tiles into a single world raster (500 meters resolution) through ArcGis "Mosaic to new raster" tool with a simple Python script. The process seems incredibly slow. Before ...
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1answer
67 views

Time required to get results by solar radiation tool?

How much does time does the ArcGIS solar radiation tool take to give solar map for day of about 50 km area?
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1answer
202 views

Slow performance with Add Join and Calculate Field?

I have a point layer and a table with approximately 100 fields. I need to join the table to the point layer based on a key field and create a new shapefile / feature class. This script has been ...
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3answers
201 views

Using Label classes vs Definition queries - which performs the best?

Which would provide the best performance for working within ArcMap with very large datasets stored in an ArcSDE geodatabase? Multiple label classes using complex SQL queries to label specific ...
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1answer
143 views

Testing point in polygon overlay performance of Intersect, Spatial Join and Near in ArcGIS for Desktop?

In answers and comments to Select points within a polygon and update attributes I think it is being suggested that Spatial Join (Analysis) and/or Near (Analysis) may be faster than Intersect ...
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4answers
210 views

Openlayers Vector Rendering

I've just added a couple of more WFS backed vector layers to a map and the performance has dropped. Whilst debugging this I've noticed that openlayers is considering every feature in the visible ...
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0answers
38 views

Problem with Performance when accessing selected Features from PostGIS layers in QGIS using Python

I have 2 PostGIS layer in my QGIS project. They have about the same amount of data and a similar structure except that layerX has its PK on a single column and layerY has its PK on 4 columns. When I ...
4
votes
2answers
153 views

What is the significance of the SDE lineage length?

ORA-55378 left a great answer to my question: Does a high number of SDE_state_lineages slow performance? But, I realized I don't really understand what lineage length means and how it affects ...
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0answers
66 views

ArcPy loops/cursors faster without background processing?

I am running loops via cursors and raw Python in Arcpy. Within the loop several processes take place, selecting shapefiles and converting to raster, clipping, running euclidean distances, extracting ...
2
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0answers
119 views

Performance issues Tilemill with PostgreSQL and large datasets

I have a Tilemill project the size of europe. I developed my style-sheet by using a smaller dataset (size auf Austria) and everything was perfect. But now I did apply the same styles to my big europe ...
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1answer
93 views

Postgres Performance with Radius Searches

Im porting an application from mysql to postgres, and have several tables with 500k+ rows in each of geo points (lat, lon). In mysql i used a bounding box query with haversine to select rows within a ...
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0answers
44 views

QGIS fTools very slow adding random points?

I am currently on windows 8.1 qgis 2.2 and almost everything I am trying to do using ftools is too slow. For example: using divaGIS world countries layer (.shp) when I try adding 500 random points ...
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1answer
247 views

ArcSDE performance and table changes on upgrade from 9.3 to 10.1?

I'm using ArcSDE 9.3 and SQL Server 2008 R2 and I want to migrate from ArcSDE 9.3 to ArcSDE 10.1. Is there any performance differences between ArcSDE 10.1 and ArcSDE 9.3 ? Is there any change ...
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2answers
201 views

What is the most efficient method to iterate geoprocessing operations through an attribute table?

I want to calculate the clipped raster layer percentage for a shapefile consist of overlapping polygons, since ArcGIS doesn't support tabulate area for overlapping features, so I used a loop to ...
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1answer
37 views

Compressing multiple static layers to single layer to make web map loading faster?

In our web application there are many layers to be loaded, this cause the loading of map very slow. I am seeking a way to compress multiple static layers to a single layer to make the loading ...
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0answers
41 views

Speeding up arcpy's TextElement.delete()

I'm making tables to go on data driven pages. For each page there are a series of tables that are produced. The elements of the tables are made using the clone method. The problem is that it takes ...
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1answer
138 views

How to automatically generate least-cost paths between several polygons?

What is the fastest way to automatically generate least-cost paths (LCPs) between several polygons with ArcGIS ? I created a python program to do this by using the functions "CostDistance" and ...