March 23, 2009
LDM version of previous report was 6.6.5. Current LDM is 6.7.0.
LDM release highlights since previous report:
The cluster approach to toplevel IDD relay, has been operational at the UPC since early summer 2005. The cluster, described in the June 2005 CommunitE-letter article Unidata's New IDD Cluster, routinely relays data to more than 550 downstream connections. Data input to the cluster nodes is approx. 3.6 GB/hr (0.086 TB/day); average data output by the cluster is approx. 406 Mbps (~4.2 TB/day); peak rates routinely exceeding 750 Mbps (~6.2 TB/day).
The following lists the breakdown by feedtype of the data being relayed by Unidata's toplevel IDD relay, idd.unidata.ucar.edu.
Data Volume Summary for idd.unidata.ucar.edu on 20090322.2120 [UTC] Maximum hourly volume 8158.960 M bytes/hour Average hourly volume 4349.157 M bytes/hour Average products per hour 186288 prods/hour Feed Average Maximum Products (M byte/hour) (M byte/hour) number/hour CONDUIT 1805.118 [ 41.505%] 4886.608 52606.213 NEXRAD2 1166.688 [ 26.826%] 1525.352 44972.213 NGRID 650.972 [ 14.968%] 1092.804 15356.596 HDS 218.344 [ 5.020%] 440.370 18361.894 NEXRAD3 210.531 [ 4.841%] 247.040 25140.170 NIMAGE 151.581 [ 3.485%] 240.715 176.851 FNEXRAD 75.659 [ 1.740%] 99.451 52.340 IDS|DDPLUS 33.528 [ 0.771%] 39.944 29377.511 UNIWISC 20.827 [ 0.479%] 28.017 18.979 EXP 10.296 [ 0.237%] 13.108 188.532 DIFAX 3.713 [ 0.085%] 12.869 5.191 FSL2 1.889 [ 0.043%] 2.081 22.149 LIGHTNING 0.010 [ 0.000%] 0.029 9.638
Currently six real server nodes operating in two separate locations on the UCAR Foothills Lab campus (in the UPC offices and in FL-2) and one director comprise idd.unidata.ucar.edu. A second and third directors have been configured for added redundancy.
The cluster approach to IDD relay has been adopted by NOAA/GSD and Penn State (using funds provided by the Unidata-administered Equipment Awards program). The cluster operated by Penn State is scheduled to assume toplevel relay responsibilities for CONDUIT data in early October.
The additional data in NEXRAD Level II products measurably increased the total volume of the IDD NEXRAD2 data feed.
Much of the work on the next-generation LDM since the last report consited of the following:
Steve Emmerson also worked on releasing the next-generation UDUNITS package, UDUNITS-2.
For previous information, please refer to the Spring 2008 User Committee status report.