Map file with 35,000+ Lines... management issue
woodbri at SWOODBRIDGE.COM
Wed Jan 23 15:46:36 EST 2008
Ok, I need to ask the obvious question, WHY? do you feel you need 658
layers. Is this because you have lots of shapefiles? and most of the
layer definitions are the same except for the data source?
For Tiger data I have 33000 shapefiles, but I only have about 20+-
layers. Are you using tileindexes? Do you know what they are? Just
trying to diagnose your situation a little better so we can help.
ritesh ambastha wrote:
> Thanks Bob,
> The map file consists of 658 Layers.
> It runs with openlayers and postgis.
> Now, am trying to sort out the best way for solving this issue.
> Your reply helped me to view at the problems+solutions in broad spectrum..
> Warm Regards,
> On Jan 24, 2008 1:04 AM, Bob Basques <Bob.Basques at ci.stpaul.mn.us> wrote:
>> Whew, 35k lines, that big. How many layers is that anyway? The Googlish
>> mapfile I just did only has 1100 lines in it, and that's mostly for
>> readability. I could probably get it down to half that size if I tried.
>> Don't know what I can contribute as a "Best Practice", because I feel that
>> in most cases, that form follows function, if you need a capability, you
>> build it. Anyway, here are some of my thoughts.
>> These same sorts of performance questions crossed my mind too. The Googlish
>> mapfile I've been working on has 72 separate STYLE definitions for example.
>> Mostly ranged around threshholding of certain styles. I can see that adding
>> in the Water bodies, Railroad, Parks, and such, is really going to make this
>> thing big. I may just do those as separate MapFiles though since GeoMoose
>> handles things like these separations very nicely.
>> These are some of the primary reasons that contributed to the way we've
>> built GeoMoose as a client and why it runs against MapServer CGI, so that it
>> can abstract the layer calls in this fashion. We're running 135+ layers
>> internally at the moment, and they all have their own MAPFILE and are all
>> called separately from the client. It has made life much easier with regard
>> to MapFile creation and maintenance, since each data custodian handles their
>> respective MAPFILE. The performance issues are minimized well since even
>> the data intensive layers are not too bad from a performance standpoint.
>> But even my Googlish looking mapfile got prettty big (in my opinion) for
>> simply displaying centerlines of streets. I've learned quite a bit from
>> these exercises about these types of questions. While I have yet to attack
>> the performance side of things, I anticpate that I'll need to segregate the
>> data out at differing thresholds in order to gain some performance boots.
>> We're all about doing dynamic requests here since many of our datasets
>> change very frequently, in some cases, down to the minute. I may look into
>> tiling at some point in the future, but it will still be only for some of
>> the layers, there will still be a need to have this dynamic request
>> structure in place.
>> Bob Basques
>> GIS Systems Developer
>> City of Saint Paul, MN
>> Powered by
>>>>> riteshambastha <ritesh.linux at GMAIL.COM> wrote:
>> Dear Readers,
>> I have developed a map file with more than 35,000 Lines. Its size will grow
>> by double/triple in next few months. Now, I am trying to tune my map file by
>> removing unwanted lines. Still, I am bit confused about its maintenance.
>> Please throw some lights over writing map files by following best practices.
>> Thanks in advance.
>> View this message in context:
>> Sent from the Mapserver - User mailing list archive at Nabble.com.
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