Hi Mark,

On Tue, Jun 12, 2012 at 6:28 PM, Mark Volz <markv...@co.lyon.mn.us> wrote:
> Thomas,
>
> Our server is behind a firewall, but anyways here is some of the information 
> that I can share which might help.
>
> Server: New Quad Core Xeon, 20 GB ram, 1Tb storage free, RAID 5
> Tiles: jpeg (source, cache format, and format used in assembling tiles)
> Grid:  County Coordinates, 256*256, extent matches the extent of the client 
> application
>
> Zoom Level, Resolution, Approximate Scale (Res*12*72)
> 0, 1024, 1:884736  (region)
> 1, 512 , 1:442368
> 2, 256 , 1:221184  (county wide)
> 3, 128 , 1:110592
> 4, 64 , 1:55296
> 5, 32 , 1:27648
> 6, 16 , 1:13824
> 7, 8 , 1:6912
> 8, 4 , 1:3456
> 9, 2 , 1:1728
> 10, 1 , 1:864
> 11, 0.5 , 1:432  (0.5 feet matches the size of the imagery)
>
> Unscientific speed results for various assemble types:
>

Even if the server is behind a firewall, can you provide the urls for
each of these test cases, I basically only need the width, height and
bbox parameters (provided they are all requesting the same LAYERS=
combination)

> Source wms server: 400-800 ms
> 1:6912 (resolution matching cache, area cached) 4-50 ms
> 1:6912 (resolution matching cache, area not cached) Cache hits are around 
> .470-1.4 seconds
> 1:7000 (forward to wms server) 500-800 ms
> 1:7000 (assemble from cache on an area already cached) 1-12 seconds (panning 
> small amounts is quicker, zooming in our out takes a while)
> 1:7000 (assemble from cache on an area not already cached) 2-14 seconds
>
> Thanks
>
> Mark Volz
> GIS Specialist
>
> -----Original Message-----
> From: thomas bonfort [mailto:thomas.bonf...@gmail.com]
> Sent: Tuesday, June 12, 2012 5:27 AM
> To: Mark Volz
> Cc: MapserverList OSGEO
> Subject: Re: [mapserver-users] mapcache - transparency, surrounding area 
> color, performance when assembling images (pink tiles)
>
> (please stay on list, you answers can help others facing the same issue)
>
> On Mon, Jun 11, 2012 at 9:26 PM, Mark Volz <markv...@co.lyon.mn.us> wrote:
>> Thomas,
>>
>> It turns out that most of my problems were when 
>> <full_wms>assemble</full_wms> was set...  apparently it defaults to jpeg 
>> when mapcache has to assemble, which was causing problems with my png 
>> caches.  I experimented with changing the default to PNG.
>>
>> I think my resolutions are set (somewhat) appropriately, for testing I am 
>> using resolutions of 1024 512 256 128 64 32 16 8 4 2 1.0 and .5.  when I am 
>> browsing at one of these resolutions mapcache is very fast.  It just seems 
>> that mapcache is slow when I am using a resolution that is slightly off of 
>> one of these.  Anyways, I just turned  forward on 
>> <full_wms>forward</full_wms>, which seems to be okay.
>
> Slightly off is expected to be a bit slower, but not very noticeably so.  
> Please to try again with some higher resolutions configured (the disk space 
> overhead for those will be negligeable), mapcache assembling should be at 
> least as fast as a normal wms server if it is allowed to hit a correctly 
> configured grid resolution. For reference, the classical mercator grid has 7 
> higher resolutions than what you have configured, which will help for 
> requests covering approximately state/country scaled getmaps.
> Can you also provide the full url for a getmap request that exhibits this 
> behavior, along with timings comparing "assemble" and "forward"
> modes.
>
> regards,
> thomas
>
>
>
>>
>> Thank you for all your help!
>>
>>
>> Mark Volz
>> GIS Specialist
>>
>> -----Original Message-----
>> From: thomas bonfort [mailto:thomas.bonf...@gmail.com]
>> Sent: Monday, June 11, 2012 9:47 AM
>> To: Mark Volz
>> Cc: mapserver-users@lists.osgeo.org
>> Subject: Re: [mapserver-users] mapcache - transparency, surrounding
>> area color, performance when assembling images (pink tiles)
>>
>> On Mon, Jun 11, 2012 at 4:32 PM, Mark Volz <markv...@co.lyon.mn.us> wrote:
>>> Hello,
>>>
>>> First,  I am having trouble figuring out how to get transparency to
>>> work in mapcache when using a Mapserver/WMS source.  Does anyone have
>>> an example of how to store a transparent mapcache with a Mapserver wms 
>>> source?
>>
>> make the tileset reference a png format, not a jpeg one.
>>
>>>
>>> Next,  The color of my cache is fine, however the surrounding area
>>> outside of the extent of the cache is black.  Can that be changed to
>>> white, or transparent?
>>
>> same as previously, configure the wms service create png not jpeg
>> <service type="wms" enabled="true">
>>      ...
>>      <format>PNG</format>
>> </service>
>>
>>
>>>
>>> Third,  Mapcache seems really slow when it needs to assemble images.
>>> I am getting plenty of pink screens, and the response time is usually
>>> greater than 5 seconds.  Mapcache is much faster when I use
>>> <full_wms>forward</full_wms>, so I know the problem is not the source wms.
>>> Does anyone have an idea as to why the performance is poor when
>>> assembling images?
>> I suspect you have defined a <grid> who's resolutions aren't of the same 
>> order of magnitude as the resolution of the getmap requests, i.e.
>> when creating the result image, mapcache has to decompress and resample a 
>> very high number of tile images. Try adding a couple of higher resolution 
>> entries to the beginning of your <resolutions> array.
>>
>> --
>> thomas
>>
>>>
>>> Thank You
>>>
>>> Mark Volz
>>> GIS Specialist
>>>
>>>
>>>
>>>
>>> _______________________________________________
>>> mapserver-users mailing list
>>> mapserver-users@lists.osgeo.org
>>> http://lists.osgeo.org/mailman/listinfo/mapserver-users
>>>
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