NOTICE: This version of the NSF Unidata web site (archive.unidata.ucar.edu) is no longer being updated.
Current content can be found at unidata.ucar.edu.
To learn about what's going on, see About the Archive Site.
NOTICE: This version of the NSF Unidata web site (archive.unidata.ucar.edu) is no longer being updated.
Current content can be found at unidata.ucar.edu.
To learn about what's going on, see About the Archive Site.
On Wed, Dec 14, 2016 at 9:13 PM, Dave Allured - NOAA Affiliate < dave.allured@xxxxxxxx> wrote: > So I think you have a read cacheing failure, due to interaction between > the ncdump read pattern, and your chunking scheme. > ... > A sampling tool found that ncdump was spending more than 96% of its time > inside an HDF5 chunk reader with decompression. Every time an HDF5 chunk > is physically read from disk, the *entire* chunk must be decompressed, even > to access a single value. You see why chunk cacheing is important. > Does HDF5 not do any chunk caching itself? or for that matter, netcdf4? Is is really up to the application level to manage the caching? that seems like handling it at the wrong level to me. -CHB -- Christopher Barker, Ph.D. Oceanographer Emergency Response Division NOAA/NOS/OR&R (206) 526-6959 voice 7600 Sand Point Way NE (206) 526-6329 fax Seattle, WA 98115 (206) 526-6317 main reception Chris.Barker@xxxxxxxx
netcdfgroup archives: