Questions tagged [performance]

Performance concerns how effectively a computing system uses resources.

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38
votes
4answers
6k views

Performance of ArcGISScripting and large spatial data sets

I am currently writing a python script using the arcgisscripting module to process a reasonably large data set (~10,000 records in total) normalised over a small number of tables, 8 in total. The ...
47
votes
7answers
10k views

Tuning PostGIS for production environments?

What PostGIS documentation have you come across that has been helpful when tuning PostGIS for a production environment? I would like to get together with my DBA to setup a Postgresql/PostGIS ...
22
votes
3answers
26k views

Performing bounding box query in PostGIS? [closed]

I have a PostgreSQL table, with almost 2 million rows, with a long-lat coordinates field in the form POINT(-73.4938 33.2405). Supposing there's a geospatial index on that field, what's the most ...
7
votes
4answers
3k views

Improving upon ArcGIS Buffer/Dissolve performance?

I'm wondering if anyone else has experienced significant performance penalties when using the ArcGIS buffer function with the 'dissolve' option on point features. My dataset is a shapefile of 260 ...
29
votes
5answers
16k views

Increasing speed of crop, mask, & extract raster by many polygons in R?

I'm extracting the area and percent cover of different land use types from a raster based on several thousand polygon boundaries. I've found that the extract function works much faster if I iterate ...
20
votes
6answers
15k views

How to improve rendering performance of a very large shapefile?

I have a polygon shapefile that has a 100MB .dbf, and 500MB .shp file component. The reason it is so large, is that it is classified as a landbase for a whole district. Everytime I view the file in ...
7
votes
1answer
2k views

Working around slow processing times in ArcGIS Spatial Analyst functions?

I am batch processing a large amount of distance functions (~50,000) using ArcGIS 9.3. In this version, using spatial analyst functions, it seems to be the case that users cannot parallelize processes ...
59
votes
7answers
12k views

Creating Vector Polygons with rendering performance like GISCloud?

I have been looking for a solid solution which would allow me to create a web map and overlay vector polygons without taking forever to load such data with the goal of allowing me to make each polygon ...
16
votes
3answers
5k views

How to speed up queries for raster databases?

I have a raster database in postgresql/postgis with these columns: (ID, rast, data_of_data). 'rast' is the column that has raster files in WKT format. An example query to find the DN value of a ...
12
votes
5answers
7k views

Compiling Python scripts (to .exe) that use ArcGIS Geoprocessing Tools?

I've been coding with Python for several months now and have developed some reasonably complex scripts for primarily geoprocessing tasks. That being said, I'm still learning a lot as I'm coming from a ...
13
votes
2answers
4k views

Lots of layers in one or multiple services? (and why)

I have a conundrum that I am getting mixed advice on how to go about. Therefore id like to put it to GIS-SE for some justified answers. Scenario: Client has a web mapping application. Does not ...
15
votes
3answers
5k views

Selecting ArcSDE polygon by point in ArcGIS Desktop using ArcPy?

I keep thinking that I must be missing something, but there does not seem to be a tool in ArcGIS 10 to select features (in particular polygons) from a layer at a point (X,Y) location via ArcPy. The ...
9
votes
4answers
9k views

How to fix performance problem in PostGIS ST_Intersects?

I'm a newbie in postgis and I have a problem in query performance. This my query: SELECT DISTINCT ON (userid) userid ,ST_AsText(position), timestamp FROM table1 WHERE ST_Intersects ( ...
6
votes
4answers
15k views

Avoiding GeoServer/Java out of heap space error?

I'm new to Geoserver, Ubuntu and Java, but have downloaded a virtual machine from gisvm.com and am getting up to speed. I got as far as configuring it with some fairly large shapefiles from a project ...
6
votes
5answers
1k views

Measuring draw time of layer in ArcMap?

I'd like to quantitatively measure the display performance of mosaic datasets, image service layers, raster layers, feature layers, etc. in ArcMap 10. How can I measure the draw time of a particular ...
12
votes
6answers
2k views

Does using RAM Disk improve ArcGIS Desktop performance appreciably?

I configured a RAM disk on a Virtual PC running ArcGIS Desktop 10 and set my HKCU\Software\ESRI\Output\TempPath to a directory on the RAM disk. It’s hard to perceive any sort improvement with that ...
12
votes
3answers
14k views

Measuring performance difference between Merge and Append in ArcGIS Desktop?

Often I find myself in a situation where I don't care whether or not my tool produces a new feature class, but I do care how long it takes to combine all of my large datasets. Does it take longer to ...
8
votes
2answers
4k views

Performance of Shapefile and PostGIS with GeoServer?

I'm going to build a web application, which will render around ten maps using GeoServer. I will be also changing the attribute data in the application for some layers. What is the recommended choice ...
2
votes
2answers
501 views

Nearest Neighbor

We've got a table of approximately 300,000 points and would like to find the nearest neighbor (within 10km) to each point in the same table. The most efficient query we've found so far is below, but ...
35
votes
2answers
17k views

Fastest way to count the number of features in a feature class?

With the introduction of the Data Access module in arcpy (30x faster search cursors), I want to know if counting features matching sql criteria is faster than the traditional MakeTableView + GetCount ...
18
votes
2answers
3k views

How is the data access cursor performance so enhanced compared to previous versions?

The data access module was introduced with ArcGIS version 10.1. ESRI describes the data access module as follows (source): The data access module, arcpy.da, is a Python module for working with ...
22
votes
4answers
6k views

How can I optimize pgrouting for speed?

I am using pgrouting on a postgis database created through osm2pgrouting. It performs very good on a limited dataset (3.5k ways, all shortest path A* searches < 20 ms). However since I have ...
9
votes
3answers
3k views

Quantitative evidence supporting Solid State Drive (SSD) adoption for ArcGIS Desktop workstations?

Has anyone seen quantitative evidence supporting the use of a SSD (solid state drive) in an ESRI ArcGIS Desktop workstation? Or any GIS workstation for that matter? I keep reading that SSDs can be a ...
11
votes
3answers
2k views

Which data format typically displays fastest in ArcMap?

My organization is working on an application running on ArcGIS Engine. Previous versions of the application used primarily Shapefiles for displaying roads, parcels, buildings, etc. Since I was ...
8
votes
2answers
9k views

Importing large dataset with osm2psql? [closed]

My question is similar to slow import via osm2pgsql to postgresql database and Optimizing osm2pgsql imports for OSM data but as we currently have quite some problems importing a large set of OSM data ...
6
votes
2answers
8k views

OpenLayers canvas renderer - redraws all features on selecting a single feature

I am currently trying to learn more about OpenLayers, and I'm coming up against performance / behaviour issues that I wouldn't expect to see. To elaborate... I have combined this example for ...
5
votes
2answers
425 views

How to speed up this script in PyQGIS?

I am a new in PyQGIS, I want to create a Point layer from a raster layer. In table of point layer created, there is 3 fields by name of "X_coord", "Y_coord" and "Azimuth", each point in Point layer ...
5
votes
2answers
4k views

Python: how to speed up spatial search (nearest point)?

I'm working on a program that determines the closest location from a given point. The point cloud I'm testing against is very big (~800.000). However, this doesn't really explain why my implementation ...
2
votes
2answers
3k views

Intersecting FeatureCollections in turf.js?

I've been playing around with turf.js and I'd like to use turf.intersect to intersect two datasets. My raw data are two polygon shape files so I converted them to geojson. I then tried to use turf....
7
votes
6answers
9k views

ArcMap, ArcCatalog slow to open on laptop with ample resources?

I have a recent installation or ArcGIS Desktop on a 64 bit Windows 7 Machine, with 8GB ram, intel core i7 processor, and a solid state drive. It takes ~2 min to open either ArcMap or ArcCatalog from ...
5
votes
2answers
916 views

Creating numpy.array with variable number of fields to test arcpy.da.ExtendTable performance?

There was anArcPy Café blog posting entitled Adding Fields: Performance Tips which advocated: Two approaches to help increase performance when adding numerous fields to a table or feature class. ...
5
votes
1answer
406 views

Only union/dissolve intersecting features to save time?

I have one table of about 300k polygons, some overlapping but most do not. I need to dissolve the overlapping ones and also keep the non-overlapping ones. I only need the geometries, no attributes. I ...
4
votes
6answers
2k views

Measuring data load and redraw times in ArcMap?

Rephrasing of the question slightly to address some issues. Is there are standard way of measuring load times for data, specifically sybolised data, within ArcMap? In particular, we're comparing ...
4
votes
3answers
7k views

How can I work with very large shapefiles (~1 GB) in QGIS?

I'm performing some basic spatial analyses on a large database of traffic injuries in California between 2003 - 2011. Because the dataset is large (nearly 1 GB of points), I'd like to first cut it ...
4
votes
2answers
489 views

Slow performing ArcGIS Near tool returns -1?

We are running an ArcGIS 10.0 geoprocessing script written in Python that (as part of many steps above & below) runs the Near tool. Both the input and output datasets (shapefiles & personal ...
2
votes
1answer
1k views

Large Dataset Buffer Help

Using ArcGIS 10.1. I have a large polygon feature class (130,000 records). I need to do an inside/outside buffer (+5 then -5 to fill in some gaps)... the process takes so long, I'm looking for a way ...
1
vote
1answer
1k 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 (Analysis)...
1
vote
4answers
248 views

When to use ArcPy over ArcMap GUI?

I've recently began trying out basic geoprocessing tools by using arcpy (clipping layers, buffering, etc). However, this seems slower than using the ArcMap GUI. Are there any advantages to using ...
11
votes
4answers
1k views

Performance of ArcGIS Engine using multiple file geodatabases as opposed to one?

I'm trying to decide the best way to organize my data for an ArcGIS Engine application. I am particularly interested in map display and query speed. Currently I have all of my data separated into ...
6
votes
2answers
3k views

Which plugin can draw topoJson right within Leaflet without conversion?

I already have asked how to reduce file size and increase performance for publishing spatial data on the web using Leaflet, here. A conversion to TopoJSON has reduced the file size by approximately ...
17
votes
6answers
9k views

Why is the performance speed between ArcGIS and QGIS so different?

Ok I am not a programmer but a prolific GIS user. I know that QGIS is written in C++ and ArcGIS in ??? but for most of my tasks lately I always try to use QGIS not only because it is free but due to ...
10
votes
5answers
1k views

How to improve performance when using ArcGIS cursors in Python with big tables?

I have a pretty big point feature class in a file geodatabase (~4 000 000 records). This is a regular grid of points with a 100m resolution. I need to perform a kind of generalization on this layer. ...
14
votes
3answers
3k views

Increasing display performance of ArcGIS Online Basemaps like Bing in ArcMap?

I'd like to know if there are ways (within ArcGIS itself) to increase the display performance of basemaps within ArcMap. The internet connection was recently upgraded, so it is much faster than before,...
4
votes
2answers
5k views

Leaflet.geojson webpage performance out of hand, how to convert to .png?

I exported some countries as a single .geojson file. The file includes every country's vertices and coordinates, as that's what a .geojson is ─ a vector file. Thing is, there are about 20 countries ...
3
votes
2answers
2k views

How to improve poor performance times for PostGIS 2.1 Tiger Geocoder?

I've recently upgraded my PostGIS DB from 2.0 to 2.1. I initially followed the instructions from Waiting for PostGIS 2.1 - Install PostGIS Tiger Geocoder as an Extension and 2.7. Installing, ...
12
votes
4answers
6k views

Fastest way to convert big raster to polyline using R or Python?

I have a big raster file (129600 by 64800 pixel) with global water bodies (1 bit values 0 and 1) and try to extract ocean and inland water shorelines. I've tried with ArcGIS and QGIS to convert from ...
9
votes
8answers
6k views

Maximizing the use of CPU

My script is intersecting lines with polygons. It's a long process since there are more than 3000 lines and more than 500000 polygons. I executed from PyScripter: # Import import arcpy import time # ...
6
votes
1answer
1k views

Optimising performance on local QGIS + PostGIS installation?

I'm learning how to manage a local PostGIS (ver 2.1) database, with spatial indexing enabled on the shapefiles that I've imported (using the PostGIS Shapefile Import/Export Manager). I have imported a ...
6
votes
2answers
2k views

Faster way to calculate slope between two points on DEM using ArcGIS for Desktop?

I'm a forester, and I do lots of work with LiDAR derived DEM's. I'm looking for a quick-and-easy tool to calculate the slope between two points. The application for this would be drawing a proposed ...
5
votes
1answer
4k views

How to find the distance to the nearest coastline from a land-based latitude/longitude point?

I'm completely new to GIS and unsure what I need to solve this problem: In the image above turquoise is actually land. Sea is white. I tried using the NASA Distance to the Nearest Coast data dump by ...