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Hi Andy, Andrew Hanushevsky wrote: > Hi Fabrizio, > > > On Mon, 17 Jul 2006, Fabrizio Furano wrote: > >> Issue 1: >> suppose that you have a cache file system with 2 dirs, where you want to >> write: >> >> oss.cache public /kanga/prd1 >> oss.cache public /kanga/prd2 >> >> it seems that if one directory of the cache file system is not writable >> (e.g. prd1 by mistake) the data server can choose to use it anyway, >> causing problems. It should detect this and choose the other one. > Yes, specifying a r/o cache makes little sense. I will have to look to see > if I can actually determine this is r/o and issue a warning and remove > that cache specification from the config. > >> Issue 2: >> let's suppose that we want 2 cache file systems in a data server, to >> avoid the "flat" allocation made by the server. Here is an example: >> >> oss.cache skm /kanga/skm1 >> oss.cache skm /kanga/skm2 >> oss.cache prd /kanga/prd1 >> oss.cache prd /kanga/prd2 >> xrootd.export /prod >> xrootd.export /skim >> >> The config documentation says (or, at least I understand from it) that >> you can pass (through the open request) the oss.cgroup directive via >> opaque information specifying the cache group you want to write to. >> Well, we were unable to make it write /prod to the cache group "prd". It >> seems that the server always arbitrarily chooses the cache directory it >> wants between all the entries. > That can be a bug as you are the first one to try this. I will have to > look at this. Does debug output show anything? > Uhm... nothing special. I included the opaque info in the destination url, specifying the file to create. >> Anyway, even if we make it work, or even if we understand why we were >> not able to, the best solution possible imho would be to associate a >> cache group to an exported directory, maybe in the xrootd.export directive. > That would be another way of doing this. > >> e.g. with directoves like: >> >> xrootd.export /prod prd >> xrootd.export /skim skm > Actually, I am in the process of merging the oss.path directive with the > export directive so that all paths need to be specified only once. So, I > would probably do something ling "cg gname" or something lik that. This sounds like a double advantage! > >> it could be possible to tell to the server to use the cache group "prd" >> to write /prod data, and the cache group "skm" to write /skim data, >> avoiding the fact that the files inside the cache fs are put all together. > Yes. > > Andy Bye Fabrizio