Performance advantage to limiting custom POI?

I'm not sure, but if they all have custom icons and/or sounds alerts then it could. If they don't, I don't see why it would matter unless you would search all the POI's at once.

I'm currently at 189,582 for all my custom POI's.

I have about 200,000 POIs, mostly schools used for my school zone alerts.

I'm just guessing but I think a TourGuide will likely cause more of a slow down than a simple POI file. But my TourGuide is my Schools file has over 170,000 points and I doubt that I see any slow down even on my slower, older devices.

Some nuvi features like myTrends, eco, etc. probably put a much more severe drain on system resources than Custom POIs.

Using my 1490LMT, I have tested more/less CustomPOI. I have noticed zero difference of the things you mention.
..Placing the most recent map updates on my SD card, boot-up time increased from 15 to 18 seconds.
And welcome to the forum. CraigW gives great advice.

I load about 30k POIs on my 855 and have no performance issues.

Assuming that there are over 9 million POIs built into the unit as it comes out of the box, I do not see how adding custom POIs could make any difference that would be noticeable. For the most part, POIs are there for routing only.

Now, as craigw surmises, TourGuides might have some impact because the unit will be checking to see if a TourGuide point of interest is within a radius distance of the unit's current location.

Proximity alerts will also require the unit to calculate distances.

However, my experience with POIs has not caused me to notice any change in the speed at which my 765T operates.

Thanks for the feedback everyone. I had been considering editing some of the coast to coast POI files to remove everything east of 90°W longitude to cut down the sheer number of POIs in places I will likely never drive. But now I think I'll just leave them alone for simplicity sake.

glad the comments helped.

That's especially true if the POI file is one that's updated often, such as the Red Light Camera file. I can't imagine having to edit that file every week.

It is much simpler to just download the file, replacing the existing file, and then run POILoader on all your files.

My TourGuide Mcdonald file has been edited. I tossed out all the provinces and Alaska and Hawaii. The gpi file size went from 2.765MB down to 2.397MB.
That is my largest Custom POI, with 15,180 locations in the original file.

I have a 60CSx and a Montana 600. I have the same map loads on both devices.

If I load all my POI on the 60CSx, the POI load will bog the unit down and slow it down overall. I have to carefully pick POI for the trip to minimize the impact on the 60CSx.

The Montana 600 has ample processing power to handle full map installs and almost 250K POI (14MB) with barely a perceptible impact on performance.

I manage both units from the same computer and load the same POI files to both units.

Just try it. It only takes a couple minutes to find out. Load it up to the max and see how it works.

I have a TomTom, not a Garmin, but I assume that they work in a similar manner, and that the consequences would be similar.

With my TomToms, I see no effect from loading additional POI files onto the device. I suppose that it *might* have an effect if I were to fill up the memory so far that there was no spare "scratch pad" space and the swapping of data into and out of the working area was affected. However, I have not seen that and don't know if it could even happen - and I keep a *lot* of POI files on my devices, including some large ones.

Where there *might* be a need for caution is in how many of the POI files you have checked to be *active* at any given time, and how many of those might be in your area. If a given POI file is set as active, then the GPS needs to continuously check the vehicle location against the locations in that file to see if they *need* to be displayed, and if an alert is appropriate. That will eat up some processor cycles that would otherwise be available for navigation, etc.

If you have a lot of *active* POI files of common locations (such as MacDonald's) and are in a major metropolitan area, there will also have to be more processor time allocated to displaying those locations on screen. I could easily see the possibility of this combination of factors impacting the performance of re-planning if a turn is missed, etc.

Personally, I try to keep all of my POI "un-selected" except those I feel that I may need at the moment. This is partially for the reasons above, but also because - in Southern California - I wouldn't be able to see the streets for the dozens and dozens of icons that would be on the screen at a given time, and alerts would be almost non-stop.

With best wishes,
- Tom -

I renamed McdonaldTourGuide.gpx to Mcdonald.gpx. and
then I removed the bmp and the wav file from my custompoi folder on my pc.
Then I ran POI loader again.
The gpi file changed from 2397kb to 2147kb.
Not much difference.

Interesting. And if you kept the bmp and wav, the difference would even be smaller and therefore there's little or no space-savings on internal (or SD) storage used by choosing straight POIs rather than TourGuides.

The unanswered question, though, is whether there's added "stress" on the GPS CPU and a slowdown or added potential for GPS freezes or reboots due to TourGuides added processor needs over an ordinary Custom POI. Testing this could require quite a bit of effort.

It's certainly possible that a Custom POI with no Proximity Alert adds near-zero processing when using the GPS, a Custom POI with an alert adds some extra processing effort, and a TourGuide may require much more processing.