Martin Dobias wrote:
On Fri, Jun 25, 2010 at 5:55 PM, Frank Warmerdam wrote:
My intent is to use two OGRLayer instances of the same layer: one
instance for handling various stuff in main thread, the other one in
worker thread for rendering. Can I expect the GetNextFeature calls to
be reentrant,
On Fri, Jun 25, 2010 at 5:55 PM, Frank Warmerdam wrote:
>> My intent is to use two OGRLayer instances of the same layer: one
>> instance for handling various stuff in main thread, the other one in
>> worker thread for rendering. Can I expect the GetNextFeature calls to
>> be reentrant, i.e. can th
Martin Dobias wrote:
Hi Frank
On Wed, Jun 23, 2010 at 4:58 PM, Frank Warmerdam wrote:
Martin,
Generally speaking it is not safe to have multiple threads making calls
into a single OGRLayer at the same time. At the very least you will
encounter the "messing up" effect on GetNextFeature(), eve
Hi Frank
On Wed, Jun 23, 2010 at 4:58 PM, Frank Warmerdam wrote:
> Martin,
>
> Generally speaking it is not safe to have multiple threads making calls
> into a single OGRLayer at the same time. At the very least you will
> encounter the "messing up" effect on GetNextFeature(), even if you
> seri
Martin Dobias wrote:
So my only problem is to avoid concurrent reads from
both main thread and worker thread. How can be this
best accomplished without serializing the access?
Your reads are eventually going to be serialized by the disk controller
anyway, so what is the problem with serializing
Hi Ed
On Wed, Jun 23, 2010 at 3:18 PM, Grissom, Edward (Ed)
wrote:
> In a previous message, Martin said:
>
>> So my only problem is to avoid concurrent reads from
>> both main thread and worker thread. How can be this
>> best accomplished without serializing the access?
>
> Your reads are eventua
Hi Ari
On Wed, Jun 23, 2010 at 7:32 AM, Ari Jolma wrote:
> Martin,
>
> Just a comment. In Geoinformatica, which uses GTK+, I've begun to address
> the same kind of problem using the functions provided by GTK+. So far I've
> not used this on rendering and I've not thought about all the consequenci
Martin,
Just a comment. In Geoinformatica, which uses GTK+, I've begun to
address the same kind of problem using the functions provided by GTK+.
So far I've not used this on rendering and I've not thought about all
the consequencies. In some expectedly lengthly GDAL operations it
provides a m
Hi all,
in my GSoC project [1] I'm trying to employ multithreading to make
rendering in QGIS both faster (on multi-core machines) and more
pleasant to use (not blocking GUI thread while rendering). I've been
successful with making that work in "ideal" conditions (no concurrent
reads/writes) and no
