HDF5 Packet Table API - C++

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1

Trying to use a packet table as a stream for writing to an HDF5 file.

Looping a sequential write of an H5T_NATIVE_UINT, but so far it seems fairly
slow compared to a C# binarywriter.

Am I using the packet table for something it was not intended for? (i.e. as
a stream writer)?

Thanks.

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2

Here is the HDF5 code I am using:

hid_t cf = H5Fcreate( "Test1.h5", H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
hid_t ptc = H5PTcreate_fl( cf, "pt1", H5T_NATIVE_INT, 4096, -1);

int x = 2;

for (int a = 0; a < 9999999; ++a)
{
  H5PTappend( ptc, 1, &x);
}

Is this appropriate usage?

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3

Hi,

Try reducing 'Chunk size' while creating a packet table.

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Best Regards,
Santosh
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4

Hi. See my other post on the topic "Performance issues with Packet Table".
I've played with chunk size, and bizarrely my first arbitrary choice of 500
seemed to give best performance, but compression is the real performance
killer.
Steve

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