<html>
<head>
<meta content="text/html; charset=ISO-8859-1"
http-equiv="Content-Type">
</head>
<body text="#000000" bgcolor="#FFFFFF">
meant to say "no special memory management issues"<br>
and (in case you actually would look at the code) mmap use is here:
<a class="moz-txt-link-freetext" href="https://github.com/burlen/SC11-100GB-Demo/blob/master/SC11DemoReader.h">https://github.com/burlen/SC11-100GB-Demo/blob/master/SC11DemoReader.h</a><strong>
</strong><br>
<strong><br>
</strong><span class="repo-root js-repo-root"><span itemscope=""
itemtype="http://data-vocabulary.org/Breadcrumb"><a
href="https://github.com/burlen/SC11-100GB-Demo"
data-branch="master" data-direction="back" data-pjax="true"
itemscope="url"><span itemprop="title"></span></a></span></span><span
class="separator"></span><strong class="final-path"></strong>
<div class="moz-cite-prefix">On 05/16/2014 10:50 AM, Burlen Loring
wrote:<br>
</div>
<blockquote cite="mid:53764FFB.6040502@gmail.com" type="cite">Hi
David,
<br>
<br>
I've used mmap with VTK in C++ for the SC11 100GB network demo.
<br>
<br>
<a class="moz-txt-link-freetext" href="http://dl.acm.org/citation.cfm?id=2287004">http://dl.acm.org/citation.cfm?id=2287004</a>
<br>
<a class="moz-txt-link-freetext" href="https://github.com/burlen/SC11-100GB-Demo">https://github.com/burlen/SC11-100GB-Demo</a>
<br>
<br>
This use was very ad-hoc and we wanted the data mapped for the
life of the app so there were special memory management issues.
<br>
<br>
patch(<a class="moz-txt-link-freetext" href="http://review.source.kitware.com/#/c/14072/">http://review.source.kitware.com/#/c/14072/</a>) would have
handled situations such as this through a callback invoked when
the data array is finished with the pointer. However, that patch
was rejected for being overkill. Instead Berk suggested that I
simply use the delete event observer, which will always result in
data being released but perhaps not as quickly as with the
callback or the method that you proposed(eg nothing happens if the
array is resized). This approach has worked well for me. I wonder
if using the delete event observer would work well in your case?
<br>
<br>
Burlen
<br>
<br>
<br>
On 05/16/2014 10:21 AM, David Gobbi wrote:
<br>
<blockquote type="cite">Hi All,
<br>
<br>
I've used memory mapped files with VTK in the past, using the
python
<br>
"mmap" object to create the map and then passing the resulting
pointer
<br>
to VTK via the SetVoidArray() method. For large files (several
GB) I've
<br>
found this to be many times faster than e.g. vtkImageReader2.
<br>
<br>
My question: has anyone used mmap with VTK in C++?
Specifically,
<br>
what I'm interested in doing is adding a new "delete method" to
the
<br>
SetVoidPointer() method in vtkDataArrayTemplate.h: it already
has
<br>
"delete methods" for "malloc" and "new", so the idea is to add
another
<br>
delete method for "mmap" that will call munmap on the pointer.
<br>
<br>
David
<br>
_______________________________________________
<br>
Powered by <a class="moz-txt-link-abbreviated" href="http://www.kitware.com">www.kitware.com</a>
<br>
<br>
Visit other Kitware open-source projects at
<a class="moz-txt-link-freetext" href="http://www.kitware.com/opensource/opensource.html">http://www.kitware.com/opensource/opensource.html</a>
<br>
<br>
Follow this link to subscribe/unsubscribe:
<br>
<a class="moz-txt-link-freetext" href="http://www.vtk.org/mailman/listinfo/vtk-developers">http://www.vtk.org/mailman/listinfo/vtk-developers</a>
<br>
<br>
</blockquote>
<br>
</blockquote>
<br>
</body>
</html>