Re: Netcdf based web application and a question
Mark Rehbein wrote:
Hi John,
About a year ago you helped me with using the Netcdf java API you are
developing.
We finally have our web application which uses the netcdf api
available for use so if you would like to see it then please visit the
following URL:
http://138.7.120.8:9555/sstatlas/do/gotoWelcome.do
We have not advertised the url yet so please do NOT publish the url to
the site just yet.
I also have a question about the NCML dataset that we are using and
its scalability.
We have a netcdf file for each month of SST data which we aggregate
with NCML and use as a dataset in the Netcdf java API. I have found
that when the dataset is used, a file handle is created to each netcdf
file defined in the aggregate. Obviously, if we have too many of these
netcdf files in the aggregate the system will run out of file handles.
I think our unix server can handle about 1024 file handles per process
but these could potentially be used up if we are running multiple
netcdf type applications on the single tomcat process.
Thanks
Mark
Hi Mark:
thanks for the update. looks pretty cool. have you studied the
performance bottlenecks at all?
i am working on a new version of ncml aggregation that will let you
specify number of open file handles. wont be done till next year
sometime. its will be part of version 2.2 I may try to multithread it.
i'd like to hear about what features in ncml you are using, since i am
making a new version and i am planning on dropping or modifying some of
the tags.
