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Hi Alessandra, He needs supervisors because he has more than 64 data nodes. You will need them too. Everything is explained in http://xrootd.slac.stanford.edu/doc/olb_config_050601/olb_config.htm in the introduction section. Andy ----- Original Message ----- From: "Alessandra Forti" <[log in to unmask]> To: <[log in to unmask]> Cc: <[log in to unmask]> Sent: Wednesday, May 24, 2006 7:12 AM Subject: Re: New xrootd development version 20060523-1741 available > Hi, > > I see you have a 3 tiers hierarchy: redirector, supervisors and > workernodes. What is a supervisor? Other configurations don't seem to have > this layer. Can supervisors be specialised worker nodes? What is olbd? and > finally is the software for redirector supervisors and data servers the > same (i.e. I install the same rpm) but configured differently? Why are you > using 2 xrootd instances per WN? Have you bound each with a different > partition? Or do they both serve all the available partitions. > > Apologies for all these questions you'll have to bear with me until I get > up o speed. > > thanks > > cheers > alessandra > > Pavel Jakl wrote: >> Hello, >> >> Yes, it is. But the plot is showing sum of usage at production and >> development cluster. I have to split the statistics into 2 plots, sorry >> about not giving you a proper plot. >> I can say, that I couldn't see what Fabrizio is talking about because we >> still don't have so many users using the xrootd. We wanted to move from >> our old solution very slowly and see the behavior of xrootd with >> increasing number of users as time goes. Users are switching from rootd >> to xrootd by their choice and I can say that this process in completely >> unclear to me :-) But the number of users is higher and higher as xrootd >> gives more advantages. >> >> Cheers >> Pavel >> >> Alessandra Forti wrote: >>> Hi Pavel, >>> >>> thanks this is very useful. Is this the STAR production cluster? I read >>> also that talk given at chep. >>> >>> cheers >>> alessandra >>> >>> >>> Pavel Jakl wrote: >>>> Hello Alessandra, >>>> >>>> Andy talked mostly about scalability and performance tests of xrootd >>>> and trying to show the behavior of xrootd at upper limits I believe. I >>>> don't know nothing about the fact that xrootd uses a lots of memory. >>>> We are using xrootd on WNs and we have deployed it on 320 nodes with >>>> about 130TB. These nodes are heavily loaded by user's jobs, mostly ROOT >>>> jobs. >>>> For your imagination, I am sending you plots being produced by really >>>> home-made monitoring with Ganglia toolkit. >>>> I also need to mention, that you have to divide these numbers by the >>>> factor of two, because we are running two instances of xrootd per node >>>> (we have a development and production cluster). You can see that memory >>>> usage is really, really small. >>>> >>>> Cheers >>>> Pavel >>>> >>>> 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 * > ******************************************* >