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I am using QGIS 1.8.0 and it runs slowly (with huge layers the size of NSW, Australia) and it appears that QGIS is limited in its RAM allocation to 128.9MB. How can I increase the speed with which it deals with such big files by allocating a larger amount of my computers power to QGIS?

I am running Windows 8 Pro (64-bit) on: - Intel Pentium P6200 @ 2.13GHz (dual core); - 2.00GB RAM - AMD Radeon HD 6300M Series

  • Engine clock speed: 500-750 MHz
  • Processing power (single precision): 80-120 GigaFLOPS
  • Polygon throughput: 125-187.5M polygons/sec
  • Data fetch rate (32-bit): 16-24 billion fetches/sec Texel fill rate (bilinear filtered): 4-6 Gigatexels/sec Pixel fill rate: 2-3
  • Gigapixels/sec Anti-aliased pixel fill rate: 8-12 Gigasamples/sec
  • Memory clock speed: 800-900 MHz Memory data rate: 1.6-1.8 Gbps Memory bandwidth: 12.8-14.4 GB/sec
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What let you to the conclusion that the RAM is limited? – BradHards Dec 18 '12 at 22:53
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QGIS isn't limited to a set amount of RAM (well apart from what the OS gives it). My current QGIS instance is using 290MB of RAM, and can reach 900MB with heaps loaded including ecws. – Nathan W Dec 18 '12 at 23:21
Can you share the dataset that you are using so we can test? – Nathan W Dec 18 '12 at 23:21
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I would also suggest to maybe pull all the data down and work in a local database, in what ever format that be, so that you don't have to rely on pulling the data over a network each time you do something. – Nathan W Dec 19 '12 at 1:01
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As it is, this question is grasping at straws and is unanswerable, so I voted to close. To improve upon the question you would need some experience in performance and memory profiling. – blah238 Dec 19 '12 at 1:30
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closed as not a real question by blah238, underdark♦ Dec 19 '12 at 6:58

It's difficult to tell what is being asked here. This question is ambiguous, vague, incomplete, overly broad, or rhetorical and cannot be reasonably answered in its current form. For help clarifying this question so that it can be reopened, see the FAQ.

2 Answers

up vote 2 down vote

I have a similar processor setup but with 6 GB ram. Most of the other parameters I can't comment on..... I find the NSW lot DP data is a burden also, I zoom to my area of interest before I turn that layer on. I find the data is not really much use at a scale greater than 1:100000

Having said that I acknowledge that I run it from a local drive.

I go with the comment above that you could copy it to your local drive, this is one dataset which you probably will never edit so there should be no issues with concurrency, version control etc.

Are you making a an A0 map or something which requires the full layer to be in focus? Note that you search the attribute table more quickly than browsing the map canvas.

I recommend the workflow above.

cheers from Narromine

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Apart from storing the data on a local disc (not USB), I would suggest using a Postgis database with spatial index (for vetor data), or a VRT (for raster data). This would prevent your QGIS instance to load the whole data and manage it by itself.

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