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[netCDF #RPP-420427]: memory leak

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  • Subject: [netCDF #RPP-420427]: memory leak
  • Date: Wed, 31 Mar 2010 09:41:29 -0600
> Here is the an example code and its output on Unbuntu 9.04. As you can
> see, the memory usage keeps growing. The versions of HDF and NETCDF
> are 1.8.4 and 4.1-snapshot2010020200, respectively. I suspect either
> nc_close() does not clean all the references to HDF objects or
> H5garbage_collect() is not doing a great job.
> 
> -Huaiyu
> 

Howdy Huaiyu!

Thanks to you and several others I did a lot of work with HDF5 objects in 
netCDF-4, making sure that I closed them all.

But there were a few activities that caused memory growth within the HDF5 
library, even though I was closing everything correctly. In those cases I 
submitted bug reports to the HDF5 team, including sample programs that 
duplicate the problem.

We believe all of the remaining problems are pretty minor. However I have just 
added code to call H5close when all netCDF files are closed. This will prevent 
the steady consumption of memory by the netCDF/HDF5 libraries, unless some 
files are always kept open.

(This change is going to be available in the snapshot release that is being 
generated now: 
ftp://ftp.unidata.ucar.edu/pub/netcdf/snapshot/netcdf-4-daily.tar.gz)

When the HDF5 team processes the remaining known memory problems, they will no 
doubt do another release. At that time we can check to see if we got all the 
leaks, or if there are still any left.

Thanks!

Ed

Ticket Details
===================
Ticket ID: RPP-420427
Department: Support netCDF
Priority: Critical
Status: Closed