Image Service Using MRF Not Displaying Complete Images

704
6
08-15-2019 08:42 AM
LorneDmitruk2
New Contributor III

Hi,

I've been testing image services using MRF files stored on Azure accessed via a file geodatabase and raster proxy files. When accessing the service a scale large enough to require accessing the original imagery not all the tiles are being returned, as shown below.   

Starting at 1:3000

1:2250

1:2000

1:1250

So depending on the scale and what area one is looking at, the missing tiles come and go. Also, the cache files seem to updating OK.

Here's another interesting effect, when the image return type is requested as JPG, some of the tiles are returning incomplete band information. 

So any thoughts about why this happening would be greatly appreciated.

Cheers

6 Replies
AbhijitDoshi
New Contributor III

Hi,

can you set the system level environmental variables 

GDAL_HTTP_MAX_RETRY = 5

GDAL_HTTP_RETRY_DELAY = 10

once these are set, restart the ArcGIS server and delete the cache, 

Regards 

Abhijit

Reply
0 Kudos
LorneDmitruk2
New Contributor III

Hi Abhijit,

With the new environment settings I'm getting the same results as before.

Cheers

Reply
0 Kudos
NicholasEverdell
New Contributor II

Hi,

We are having the exact same issue using AWS (S3, EC2, Raster Proxy & MRF Cache on EBS)

Gordon Sumerling
Peter Becker

Vinay Viswambharan

Any ideas on how to resolve this issue?

Thanks,

Nic

Reply
0 Kudos
GordonSumerling
Esri Contributor

Hello Nic,

In the Mosaic dataset on the defaults tab there is a setting "Maximum number of Rasters Per Mosaic" by default this is set to 20. Recommend increasing this to 200. You should then see all of your rasters

Gordon

PeterBecker
Esri Regular Contributor

Looks to me like on one of the following:  (most probably 2)

1- Looks like the source data may consist of a large number of small tiles. If this is the case check the level at which overviews are created. The smaller the tiles the larger the resolution the overviews need to be. If you dont have sufficient overviews then system will need to open many files which can degrade performance and lead to issue if 'Max number of rasters per mosaic' is not large enough. If the source is many tiles consider mosaicking them together into much larger tiles (same projection/pixel alignment).

2- If the issues is with raster proxies then check Appedix D in the Optimize Rasters documentation. The issue is often related to running desktop and server on the same machine that causes locks on the cached files. This may have caused corruption of the tile cache indices. Delete the cache. Also ensure the cache is on a local drive (preferably a fast ephemeral drive). Do not point the cache to a network drive or some location shared with multiple machines.

NicholasEverdell
New Contributor II

Thanks All for the responses, much appreciated.

We have what Peter mentioned and the MRF cache is on a shared folder as we have a multi-machine ArcGIS Server site in AWS, these are in an auto-scaling group and use local service accounts. This meant that when multiple users are using the service at once multiple of these service accounts are trying to Read/Write to the MRF cache at the same time which is causing the read errors.

We moved the service over to a single machine ArcGIS Enterprise build and had no dramas at all.

 

We also followed Gordon's advice and increased the maximum number of rasters to ensure we don't have any issues in the future either.

Reply
0 Kudos