Speed of address find and route calc?

Ponty

As a new user I was wondering if anyone could shed light on wether its the size of the map (UK full) that slows the address search and route calc down to almost snail like or the fact that I have to use the CF card?

I have the Wales (16MB) map loaded into internal memory and its more than adaquate.....with the full UK map on CF its dog slow?

Assuming its the map size, and I install the whole country in segments, will the route search jump between maps or do I have plot seperate routes for each map?

Or is there anyway of speading up the CF storage?

Thanks

GFawkes

Ponty, See this post.

Lots of people have experienced problems with CF cards. It could be the type of card, or if you have an iPAQ, a downgrade of the ROM may do it.

Rgds.

aero

The problem with the new ROM on the iPaq's was related to accessing information from the SD slot. You may not find that downgrading your ROM will help if you store your maps on a CF card.

Ponty

I'm using a DELL Axim with ROM A02, but am about to try ROM A03 that I have just downloaded.

32mb Map segments on the CF card are OK, but the full UK map is very slow...A

Does formatting the SD/CF card with a bigger cluster size improve performance on a big file such as the UK map?

Boxbrownie

Hi Ponty

How slow is slow? I too have the Axim (400) and find the route calculation quite fast, and rerouting during journey cock-ups to be very fast indeed. I calculated a route from A'Chill (Highland) to Zenner (Penwith) just as an experiment for comparison and it took exactly 30 seconds, not too bad I though for over 497 miles.

Best regards David

Boxbrownie

BTW, I have the whole of the UK map on one 128mb integral CF card.

Best regards David

DavidW

The "iPAQ problem" is limited to the x.1x series ROMs on the 3900 series (that is 395x ROMs 1.10 and 1.11, and 397x ROM 2.10). It affects the SD slot only - the drivers in those ROMs are slower at SD memory access (in some cases significantly slower) than the original x.00 ROMs (395x ROM 1.00 and 397x ROM 2.00). Unfortunately, switching between x.00 and x.1x ROMs (either way) requires a hard reset and reinstallation of all your software.

Any 395x user on 1.10 is well advised to switch to 1.11 - the reason for the release of 1.11 was to solve a bug in 1.10 that often reduced the processor speed to 300MHz. 2.10 on the 397x was not affected, hence there is no 2.11 ROM for that hardware. (The 1.xx ROMs are for non-Bluetooth machines, the 2.xx ROMs are for Bluetooth machines).

There are also issues with Sandisk SD cards performing significantly slower than other brands on just about any hardware. (Beware - some other major brands might be relabelled Sandisk - recent examples of Lexar 256MB cards often seem to be relabelled Sandisk).

Dell Axim X5 machines are unreliable on certain brands of SD card - particularly Sandisk and rebadges thereof (though this problem is not limited to Sandisk cards). This problem is being discussed on the Dell Forums.

Any storage card that is fragmented will hurt performance. This applies to CompactFlash and SD memory - or any other sort of memory you may be able to connect to your Pocket PC! Defragmenting any storage card you have maps on is highly recommended.

Any storage card, be it SD or CompactFlash is *much* slower than built in memory. The RAM on my iPAQ 3970 is readable at about 21 MBytes/second and writable at around 8.25 MBytes/second (according to Pocket PC Mark 1.03). Seek performance is measured at around 260,000 positions per second - I am unclear precisely what sets the limitation on seek performance and what impact this has.

No storage card I know of on a Pocket PC is capable of more than about 1.3 MBytes/second read speed - which, I would think, is the most crucial metric for TomTom Navigator (what Pocket PC Mark doesn't give you any idea of is how much processor usage memory card reading requires - that is also relevant here). Seek performance for all storage cards I've tried on my 3970 is comparable to internal memory.

Internal file stores (such as the iPAQ File Store on an iPAQ) are typically extremely slow at writing, but return reasonable read performance - my 3970's iPAQ File Store benchmarks at 0.75MBytes/second. The seek performance is much lower than any other memory I have on my iPAQ - this could hurt TomTom Navigator 2 performance if I used this memory for a 16MB map.

Using a larger map does hurt performance, particularly on address lookups, because there is more data to be searched. TomTom Navigator does a fuzzy search when you input place names, adding, I'd expect, something of an exponential effect to search times as map size incrases.

It must be said that 1MByte/second read performance is not that sluggish, though there's no way flash memory is going to match the speed of RAM.

Hopefully this throws a little more light on this aspect of performance, at least as I understand it.

David

Ponty

BoxBrownie

Thanks for that, I'm just running the route you suggested......and its taking a lot longer on my unit? It started off very slowly, then jumped from 400 miles to go to nearer 150 and then became very sluggish again. Seemed to stick at around 72 miles to go, number of roads moving but not miles? Didn't time it exactly but around 8 mins for the same route (speed set @ 400mhz)

Are there any options which can be configured to speed it up? (Route re-calc set to Fast)??

Just did a trip from Bournemouth to Abernant S.Wales, and set off from B and said navigate to home. Route calculation took so long that by the time it had completed the route, my actual position was so far away it just kept re-calculating and neber actually got to navigating?

Any help greatly appreciated?

Dave

DavidW

A'Chill is not a great place to use in any tests - as it's on a little offshore island. Version 2.22 will say "no route found" if you try to calculate A'Chill to Zennor - though I see the attraction of choosing the first and last places in the database. Indeed, the routing algorithms have changed somewhat in 2.22, so comparisons between that and earlier versions are probably not valid.

I'd suggest Land's End to John O'Groats if you want a long route!

A 'stick' is normal sometimes - so long as the number of roads is increasing, it seems to mean that Navigator is weighing various options and hasn't settled on one yet.

Ponty - as your setup is particularly slow, I suspect the blame will lie with your storage card. Defragmenting would be a good start (if you haven't got a defragmentation tool, wipe the card and install the map first).

So far as routing yourself home goes, on a complex route in particular I'd try to plan the route before setting out. Planning a route as you're travelling can challenge the setup rather!

You can plan your route using the last GPS location before ever getting to the car.

David

Boxbrownie

DavidW

Well it worked in my set up flawlessly (version 2.22 (358)). No problems with "no route found" here thats for sure.

Best regards David

Fuego

I take it everyone is using "strict calculation", "quickest route", and latest version, otherwise comparisons are meaningless.

On an iPAQ 3870 (2.20.21 ROM), with full GB map on an 128MB SD card (newly formatted), A'Chill to Zenner took 9 mins 17 secs to "No route found".

So I wouldn't say that the problem with slow SD access is confined to 3900s.

In use, though, I find the response tolerable.

DavidW

I've been consistently using Quickest Route and Normal, which are the defaults. All the results I've posted so far are using those settings and I've been using 2.22 since a couple of days after it released (previously I was using 2.05).

If you select Strict you get a warning about speed on long routes in particular. You have to dismiss this (either until you re-enable all disabled warnings or every time you calculate) before calculation will proceed.

I ran a test on A'Chill to Zennor using Strict on my setup and it is very much slower! It took 9 minutes 24 seconds before the error, having analysed something like 450000 roads. Normal, on the other hand, takes 2 minutes 05 seconds before the error having analysed something like 190000 roads.

The configuration of my 3970 is not that standard - for a start I have network card drivers active which I often forget to disable by ejecting the card (though on both these cases, I had ejected the NIC), also my SD card setup is probably not that standard (I have FAT32 with 2KB clusters on my main 256MB card because the card is used for things other than TomTom maps for which the large cluster sizes ideal if you're just using the card for maps and MP3s would lead to unacceptable amounts of slack space). I do know that the maps on my card are defragmented.

I have a great deal of software installed on my machine, some of which is running in the background all the time (like the Pocket PC component of Pocket Controller - Professional).

If I remember, I do eject my network card, disable CheckPOInt, and don't have my CompactFlash GPS connected when running the tests. I had done all three for the results quoted above - the iPAQ's Bluetooth radio was also off.

I don't have the luxury of a spare iPAQ and spare 128MB or bigger SD card to hard reset and install just TomTom Navigator to run comparative tests.

Fuego - the 3800 series are known to have a very slow SD interface. The difference is that on the 3900 series, there is a problem that the new SD drivers in the x.1x ROMs slow down SD access - significantly in some cases.

On the 3800 series, it's more a hardware issue; I've heard it said that, for a start, the hardware is only capable of SD access in 1 bit mode and not in 4 bit (nibble) mode, which will place limits on throughput. I expect there are differences in SD performance between the drivers in different ROM versions, but I'm not aware of such great differences as between 3900 series ROM versions.

That said, I expect even on the 3800 series the difference between slow (usually Sandisk and relabels thereof) and faster SD cards will show sometimes.

What brand is your card, Fuego, and what kind of markings are there on the back - particularly anything that looks like a batch or serial number?

As you say - in use, you find the response tolerable, also I guess such long routes are not the sort of thing you plan day to day. They certainly aren't for me (and if you did need to plan such a long route, you could do it out of the car so that when you get in the car, you're ready to go).

David

Boxbrownie

DavidW & Ponty

Tried again today with the same setup in TT2 as before which are the defaults as in DavidW test, and it took 2min50 sec, no idea why the difference from my first test, but it still calculated the route with no errors at all.

Best regards David

aero

If you navigate to A'Chill the 'place' you get the 'no route found' error. But if you navigate to a road near A'Chill it will plan the route, which is what I did to start with but I don't think it is actually in A'Chill.

I'm being vague 'cos I don't have my pocket pc with me to check details.

Boxbrownie

Hi Aero,

Both time I have calculated the test route I went for the town and the first road on the list (seemed logical to go from a road in the town!), the third time the calculation took 2m5sec (Axim x5 400mz/128m integral CF/TT2/no other apps running).

Best regards David

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