Hi,
I have some performance problems after upgrading to thredds 4.6.1.
I'm aggregating a large dataset with a joinExisting aggregation. Reading
the metadata from the aggregation took, with thredds 4.3.23, about 0.1s
(first time up to 7s). After upgrading to 4.6.1, the same request takes
20s (second time, first time not measured) and is unusable slow. A
'ncview' of the aggregated dataset is no longer possible.
Suspecting some caching problems, I followed the guidelines in
http://www.unidata.ucar.edu/software/thredds/current/tds/reference/ThreddsConfigXMLFile.html
The aggregation-cache contains two files
$ ls -l file-lustre-mnt-heikok-FAUNA-mbr000_all.ncml
lustre/mnt/heikok/FAUNA/mbr000_all.ncml
-rw-r--r-- 1 tomcat7 tomcat7 74339 May 20 09:43
file-lustre-mnt-heikok-FAUNA-mbr000_all.ncml
-rw-r--r-- 1 tomcat7 tomcat7 74131 May 20 10:01
lustre/mnt/heikok/FAUNA/mbr000_all.ncml
(I guess the first one is thredds 4.3, while the second one is thredds 4.6)
The ncml-file is:
<netcdf xmlns="http://www.unidata.ucar.edu/namespaces/netcdf/ncml-2.2";>
<aggregation dimName="time" type="joinExisting">
<scan location="." regExp=".*snapMet000\.nc$" subdirs="true"/>
</aggregation>
</netcdf>
It is aggregating 4575 files, each about 1.3G.
The requests according to the logs are:
2015-05-20T09:49:17.111 +0200 [ 372240][ 281] INFO -
threddsServlet - Remote host: 157.249.113.42 - Request: "GET
/thredds/dodsC/lustreMnt/heikok/FAUNA/mbr000_all.ncml.dds HTTP/1.1"
2015-05-20T09:49:17.116 +0200 [ 372245][ 281] INFO -
threddsServlet - Request Completed - 200 - -1 - 5
2015-05-20T09:49:17.117 +0200 [ 372246][ 282] INFO -
threddsServlet - Remote host: 157.249.113.42 - Request: "GET
/thredds/dodsC/lustreMnt/heikok/FAUNA/mbr000_all.ncml.das HTTP/1.1"
2015-05-20T09:49:17.131 +0200 [ 372260][ 282] INFO -
threddsServlet - Request Completed - 200 - -1 - 14
2015-05-20T09:49:17.134 +0200 [ 372263][ 283] INFO -
threddsServlet - Remote host: 157.249.113.42 - Request: "GET
/thredds/dodsC/lustreMnt/heikok/FAUNA/mbr000_all.ncml.dds HTTP/1.1"
2015-05-20T09:49:17.138 +0200 [ 372267][ 283] INFO -
threddsServlet - Request Completed - 200 - -1 - 4
Best regards,
Heiko
--
Dr. Heiko Klein Norwegian Meteorological Institute
Tel. + 47 22 96 32 58 P.O. Box 43 Blindern
http://www.met.no 0313 Oslo NORWAY
