My understanding is that this is NOT using mmap calls to implement the CORE driver.
The core driver uses HDF5 library internal functionality to capture all write calls in a malloc'd (and realloc'd) buffer (of sorts). When the file is closed, if you set backing store, that buffer gets written to disk in a single I/O request. Thats because the buffer itself is a bit-for-bit image of an actual on-disk HDF5 file. On read, if you use core VFD, then the whole file gets read into memory in a single I/O request and then all operations on the "file" there after just interacting with the buffer in memory. Again, no mmap calls here. There is no memory mapping of the file going on. Mark From: Hdf-forum <[email protected]<mailto:[email protected]>> on behalf of "Ryland, Andrew" <[email protected]<mailto:[email protected]>> Reply-To: HDF Users Discussion List <[email protected]<mailto:[email protected]>> Date: Thursday, March 10, 2016 8:27 AM To: "[email protected]<mailto:[email protected]>" <[email protected]<mailto:[email protected]>> Subject: Re: [Hdf-forum] HDF5 and memory mapped files on Windows Timothy, Thanks for the response. I read it the same way you did in that the library will create the “in memory” file. But is it a memory mapped file or an array of sorts? Because of my lack of understanding here I asked the question about if I created a memory mapped file then could I have the hdf5 library use that. Andrew
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