Re: [netcdfgroup] slow reads in 4.4.1.1 vs 4.1.3 for some files

• To: Charlie Zender <zender@xxxxxxx>
• Subject: Re: [netcdfgroup] slow reads in 4.4.1.1 vs 4.1.3 for some files
• From: Chris Barker <chris.barker@xxxxxxxx>
• Date: Tue, 13 Dec 2016 09:54:04 -0800

if I understand the question, this is read times -- is this in fact with
exactly the same files? In which case the chunking is already set.

less performant decompression??

sounds like the binary search is needed.

Is EVERYTHING else the same? disk system, OS, etc?

-CHB


On Tue, Dec 13, 2016 at 9:21 AM, Charlie Zender <zender@xxxxxxx> wrote:

> Hello Simon,
>
> Since both files are netCDF4 compressed that
> means they use chunking. My wild guess is that
> different chunking defaults cause the observed
> change in dumping time. You can see the
> chunk sizes employed with ncdump -s or ncks --hdn,
> and you can play with the chunk sizes/policy
> with either.
>
> Charlie
> --
> Charlie Zender, Earth System Sci. & Computer Sci.
> University of California, Irvine 949-891-2429 )'(
>
>
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-- 

Christopher Barker, Ph.D.
Oceanographer

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• Follow-Ups:
  • Re: [netcdfgroup] slow reads in 4.4.1.1 vs 4.1.3 for some files
    • From: Ed Hartnett

• References:
  • Re: [netcdfgroup] slow reads in 4.4.1.1 vs 4.1.3 for some files
    • From: Charlie Zender