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Hi Fabrizio, so the memory depends on how well the files are distributed and the replicas? I have 1000 nodes (2000 cpus). I can well think that it will never happen that 1999 processes try to access 1 xrootd instance. But it might be over 100. I guess it is matter of tuning. cheers alessandra Fabrizio Furano wrote: > Hi Alessandra, > > typically the memory needs of a server are proportional to the number > of clients and to the ongoing activity rates. For a small number of > clients (let's say 1-100) the memory needs are quite low. I've done many > many stress tests in a pIII machine with 256 megs with no problems at > all. The memory becomes an important parameter when you plan thousands > of clients per server. > > Fabrizio > > Alessandra Forti wrote: >> Apologies that worries me in using xrootd on the WNs.... >> I'm a bit confused right now :( >> >> Alessandra Forti wrote: >>> Hi Peter, >>> >>> after yesterday I also remember that the second thing that worried me >>> in using dcache on the WN is a comment Andy made about the use of >>> memory in his talk at CHEP I believe. He said it xrootd uses a lot of >>> memory but there weren't number specified. >>> >>> My system is double cpu with 2GB of memory per cpu. Considering that >>> an atlas job can use more than 1 GB we are now at 1.1 I thik. Will it >>> be enough? I think so but I just wanted to check. >>> >>> cheers >>> alessandra >>> >>> >>> Peter Elmer wrote: >>>> Hi All, >>>> >>>> There is now a new xrootd development version: xrootd >>>> 20060523-1741, please see: >>>> http://xrootd.slac.stanford.edu/download/20060523-1741/ >>>> >>>> for downloads. >>>> >>>> Relative to the last development build (20060418-0404) this >>>> includes a variety of small bug fixes, plus one important one for >>>> the redirector. See >>>> the xrootd.History file for more details. I've included a link to the >>>> SL3 debuginfo rpm on the rpm page. (Although I've not tried it myself, >>>> so I have no idea if it works! Feedback is welcome.) >>>> >>>> Gerri, if it is still possible, you could add this to the next ROOT >>>> build, too. >>>> >>>> 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. >>>> >>>> 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 >>>> ------------------------------------------------------------------------- >>>> >>> >> -- ******************************************* * Dr Alessandra Forti * * Technical Coordinator - NorthGrid Tier2 * * http://www.hep.man.ac.uk/u/aforti * *******************************************