Thanks, Even. I think I've got my head around it. Since I've never written
a driver, I've never fully learned the difference between IReadBlock and
IRasterIO or where one is used instead of the other. But I'm learning that
now.
On Fri, Apr 19, 2024 at 9:35 AM Even Rouault
wrote:
>
> Le 19/04/202
Le 19/04/2024 à 17:28, Sean Gillies a écrit :
Even,
Does the shared attribute of a VRT sourceFilename element not affect
caching at all?
If shared is set to 0, then one GDALDataset per VRTSource will be
opened. This has little benefit.
The scope of sharing was initially greater since it e
Even,
Does the shared attribute of a VRT sourceFilename element not affect
caching at all? Is the cache avoided so that potentially stale data isn't
propagated, or for other reasons?
On Fri, Apr 19, 2024 at 9:09 AM Even Rouault
wrote:
> Sean,
>
> Within a given GDALDataset opened on a VRT, if t
Sean,
Within a given GDALDataset opened on a VRT, if the VRT references
several times the same source, only one GDALDataset will be opened for
it, so you may benefit from the block cache mechanism (if it is
triggered. VRTSource::IRasterIO() calls IRasterIO() on the source band,
which doesn't
Happy Friday, folks!
Are the source rasters of a VRT added to the block cache such that
different VRTs using the same source can avoid reads from disk or the
network? Or is it intended that the VSI cache covers this need instead?
Thanks,
--
Sean Gillies
_
