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Hi, maybe you don't miss anything. I suspect that you found a way (Infiniband) to greatly confuse the trivial async read ahead algorithm I coded for the first version of the async read ahead. I may be wrong, of course. In any case xrdcp does not need read ahead at all so it's better if I make it an option, as it's needed in other cases also. Async read ahead could be a help if you have an application which processes the data, otherwise it's useless. If you set the debug level to a higher value (-DI DebugLevel 1), 1 should be sufficient, xrdcp will print you the cache statistics, so we can learn something to tune this strange async thing if that is the source of the overhead. Would you do this on your setup please? Fabrizio On Tuesday 03 May 2005 12:00 pm, Ulrich Schwickerath wrote: > Hi, > > I made a quick first test running the new version on an GB Ethernet link. I > just copy a 1GByte file from my server to local /dev/null. While with > 20050413-0433 I got > > $ time bin/arch/xrdcp root://iwrcgtest.fzk.de//tmp/testfile.dat > /dev/null > > real 0m10.909s > user 0m1.150s > sys 0m0.720s > > with the new version I get: > > [schwicke@iwrcgop027:/home/schwicke/Progamming/xrootd]$ time > bin/arch/xrdcp root://iwrcgtest.fzk.de//tmp/testfile.dat /dev/null > [xrootd] Total 1024.00 MB |====================| 100.00 % [36.6 Mb/s] > > real 0m29.377s > user 0m1.670s > sys 0m1.190s > > Going to quiet mode does not help (my first thought since I work remotely): > $ time bin/arch/xrdcp -s root://iwrcgtest.fzk.de//tmp/testfile.dat > /dev/null > > real 0m28.147s > user 0m1.150s > sys 0m0.380s > > The test is done on Sun V20z dual Opterons, both for server and client, > using the onboard GE link. > > Did I miss something ? > > Thank's, > Ulrich > > On Monday 02 May 2005 17:04, Peter Elmer wrote: > > Hi All, > > > > There is now a new development version of xrootd (20050502-0000). This > > version contains a lot of new code, so it is meant for testing rather > > than production use. For production use, please try version 20050328-0656 > > instead. > > > > The changes include: > > > > o compilation fixes for gcc4 > > o updates to XrdClient for async read-ahead > > o updates to xrdcp from Andreas Peters > > o Many updates to scripts in XrdMon package > > o Code cleanup fixes (from Gregory Sharp) > > o Several fixes for minor bugs, etc. > > > > We should start testing this (including compilation on the full set of > > ROOT platforms) as I'd like to try to turn out a new production release > > in the next week or two. > > > > For the full set of changes and links to rpms/tarballs to download see > > the the xrootd web page and/or version history: > > > > http://xrootd.slac.stanford.edu > > http://xrootd.slac.stanford.edu/xrootd.History > > > > Let us know if there are problems. > > > > thanks, > > Pete > > > > ------------------------------------------------------------------------- > > Peter Elmer E-mail: [log in to unmask] Phone: +41 (22) 767-4644 > > Address: CERN Division PPE, Bat. 32 2C-14, CH-1211 Geneva 23, Switzerland > > ------------------------------------------------------------------------- -- -------- Fabrizio Furano INFN - Istituto Nazionale di Fisica Nucleare [log in to unmask]