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NOTICE: This version of the NSF Unidata web site (archive.unidata.ucar.edu) is no longer being updated.
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To learn about what's going on, see About the Archive Site.
> I read a single (lat, lon) point from a file at a time for the whole available time period Yes, that pattern is why your reads are so slow. Look at how the data is laid out: float u10m(time=5088, latitude=103, longitude=122); So, if you're reading all values for a single (lat, lon) point, you are accessing the array like so: u10m[0][lat][lon] u10m[1][lat][lon] u10m[2][lat][lon] ... u10m[time-1][lat][lon] Those values are physically located far apart within the file, preventing effective buffering due to the non-sequential reads. Chunking won't help you here; you'll need to select the data layout that suits your read pattern. This might work better: float u10m(latitude=103, longitude=122, time=5088); Cheers, Christian On Wed, Feb 18, 2015 at 11:51 PM, Antonio Rodriges <antonio.rrz@xxxxxxxxx> wrote: > P.S. > > And that speed (~700 ms) is both for chuncked and unchunked data so I > decided that is was "slow" for the chunked file since it is considered > more optimized for this read pattern. >
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