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>To: address@hidden >From: Steve Carson <address@hidden> >Subject: Re: 20020128: test case for netCDF/NFS write >Organization: RAP >Keywords: NFS performance test Steve, > I think I got it there. It's called "netCDF_NFS_example1.tar". > There is also a file called "netCDF_NFS_example.tar", of zero > size, created by my first attempt from a machine that did not > have 'ncftp'. Regular ftp has a problem getting stuff out through > the NCAR firewall. > > The tar file is about 22MB. That's because it includes an > example MM5 output file. When you run 'mm5_to_nc', you'll > need about another 13MB of space for the output file. > > Check the README file for details, and let me know if I forgot > anything. And let me know if you'd like me to send an e-mail > about this episode to 'support@unidata' for tracking purposes. I ran your test in a local directory (/buddy/russ on buddy) and NFS-mounted directories on two other machines in our machine room (/scratch/russ on zero, /data/tmp on shemp). $ df -k /buddy/russ /scratch/russ /data/tmp Filesystem kbytes used avail capacity Mounted on /dev/dsk/c1t1d0s7 13838253 1905818 11794053 14% /buddy zero:/export/scratch 5546862 5414219 77175 99% /scratch shemp:/export/data 17658298 13777076 3704640 79% /data The machines buddy, zero, and shemp are all Solaris platforms, running "uname -a" on each machine gives: SunOS buddy.unidata.ucar.edu 5.8 Generic_108528-12 sun4u sparc SUNW,Sun-Blade-1000 SunOS zero.unidata.ucar.edu 5.6 Generic_105181-30 sun4u sparc SUNW,Ultra-2 SunOS shemp.unidata.ucar.edu 5.7 Generic_106542-18 i86pc i386 i86pc Here's the results of running your test script 3 times on each test $ ./test.mm5_to_nc.sh Reading from :'./' Writing to :'./' 2.15u 1.32s 0:10.56 32.8% nfstest$ ./test.mm5_to_nc.sh Reading from :'./' Writing to :'./' 1.97u 0.81s 0:09.68 28.7% nfstest$ ./test.mm5_to_nc.sh Reading from :'./' Writing to :'./' 2.09u 0.75s 0:10.24 27.7% nfstest$ ./test.mm5_to_nc.sh /scratch/russ Reading from :'./' Writing to :'/scratch/russ' 2.12u 0.66s 0:13.39 20.7% nfstest$ ./test.mm5_to_nc.sh /scratch/russ Reading from :'./' Writing to :'/scratch/russ' 2.09u 0.53s 0:12.04 21.7% nfstest$ ./test.mm5_to_nc.sh /scratch/russ Reading from :'./' Writing to :'/scratch/russ' 2.18u 0.53s 0:12.04 22.5% nfstest$ cp MMOUT_DOMAIN_4km.20020105.060000 /scratch/russ nfstest$ ./test.mm5_to_nc.sh . /scratch/russ Reading from :'/scratch/russ' Writing to :'.' 2.13u 0.79s 0:07.68 38.0% nfstest$ ./test.mm5_to_nc.sh . /scratch/russ Reading from :'/scratch/russ' Writing to :'.' 2.06u 0.72s 0:10.91 25.4% nfstest$ ./test.mm5_to_nc.sh . /scratch/russ Reading from :'/scratch/russ' Writing to :'.' 1.96u 0.68s 0:09.14 28.8% nfstest$ ./test.mm5_to_nc.sh /data/tmp /scratch/russ Reading from :'/scratch/russ' Writing to :'/data/tmp' ERROR - umalloc Cannot perform malloc, size = 1905120 Program will now segv for debugging. 1.16u 0.19s 0:02.78 48.5% nfstest$ ./test.mm5_to_nc.sh /data/tmp /scratch/russ Reading from :'/scratch/russ' Writing to :'/data/tmp' 2.14u 0.70s 0:20.03 14.1% nfstest$ ./test.mm5_to_nc.sh /data/tmp /scratch/russ Reading from :'/scratch/russ' Writing to :'/data/tmp' 2.09u 0.60s 0:14.70 18.2% nfstest$ ./test.mm5_to_nc.sh /data/tmp /scratch/russ Reading from :'/scratch/russ' Writing to :'/data/tmp' ERROR - umalloc Cannot perform malloc, size = 1905120 Program will now segv for debugging. 0.82u 0.46s 0:07.76 16.4% The first time I got the "ERROR - umalloc" I was a little surprised since buddy has a Gbyte of memory, but I deleted some big files in /tmp which is mounted in swap space to see if that would clear up the problem, and maybe that fixed it. But then the same message occurred again a couple of runs later. I tend to have a lot of applications running in a lot of windows (emacs, netscape, FrameMaker, Java apps, exmh, ...), but I don't know if that explains it. Also, I should tell you that the machines zero and shemp are pretty busy. Especially zero, which is our main file server, has lots of disk activity. The shemp system is an experimental data server on which we ingest lots of real-time data from radars, models, and bulletins. Given how busy zero and shemp are, the above timings look OK to me, and don't seem to indicate any great slowdown using NFS. I asked Mike Schmidt about whether any special tuning had been done for our NFS setup and he said nothing much, just keeping patches up to date. But feel free to contact him about specific configuration questions. --Russ