CIAndrew


Hello All,

I looked through the documentation but didn't find an answer.

Does the NumServers parameter for tileSourceSpec apply when the tiles are served from a web farm

It says that the severs need to be named Server0, Server1 etc.. which seems like it would force alot of people to rename servers :)

Any help understanding the deployment aspect of tile server would be appreciated.

TIA

Andrew




Re: TileSource on server farm

Brian_Flood


hi andrew

I believe it appends the value of the server (1,2,3 etc.), so you could use any server name you wanted. However, as you said, this would probably entail renaming servers anyway to get the number portion added. You can use a custom GetTilePath function and create your own round robin system based on your own server names. The tiles would not be viewable in VE3D though.

a nice feature for the future would be a user definable array containing server names. The api then appends these values instead of the standard tiles0, tiles1, etc.

cheers

brian







Re: TileSource on server farm

CIAndrew

Thanks for the info Brian. I agree that us specifying the server names would be the a great feature.

I guess the VE server makes calls to all servers simultaneously (in an async fashion) so having a server farm behind a load balancer would just look like one server to it and the tile rendering speed would be like there was one server only.

Thanks again,

Andrew






Re: TileSource on server farm

Brian_Flood

yea, I hope they add something like that to the api, it wouldn't take much and would be pretty helpful to those with existing servers.

also, the VE javascript sets the src of each image and it's the browser that actually makes the async calls to get the images. IE follows the 2 HTTP connection limit per domain so it can only get 2 images at a time. Changing the sub-domain via the server names allows the browser to circumvent this limit and request 2 per tile server. Both MS and Google seem to like about 3-4 sub domains per map, so I'm guessing that after 8 concurrent image requests, you 'll get diminishing returns.

cheers

brian