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Hi Artem, yes, it is. For other commands just type "help" at the command prompt. If you have any problems, let me know. Fabrizio Artem Trunov wrote: > Hi,Andy! > > Is it available via command line interface? > > artem. > > On Wed, 25 Oct 2006, Andrew Hanushevsky wrote: > >> Hi Pavel, >> >> Yes, look at XrdClientAdmin.hh. The XrdClientAdmin interface has a >> Prepare() method that allows you to pass a list of files. This list is >> passed to xrootd which then locates the files and locates them. If you >> also specify kXR_stage then the files will be staged if not on disk. There >> are additional options but for now this should be enough to get you going. >> >> That said, what we have found is that unless you have taken great care to >> group files that will be likely used together on the same tape (something >> we find difficult to do), the probability of improving tape access is >> rather low unless you get a huge list of files into HPSS. That in itself >> causes other problems. >> >> Andy >> >> On Wed, 25 Oct 2006, Pavel Jakl wrote: >> >>> Hi Andy and others, >>> >>> I would like to discuss the topic of having a possibility to "prepare" a >>> list of files before user's jobs processing or at the beginning of the >>> job. The fact why I am rising this topic is a optimization of the >>> access to our tape system (HPSS). >>> >>> What we are doing now is that we organize the requests in a fashion that >>> we have as many file requests as possible on the same tape at HPSS and >>> therefore achieve better IO performance. Of course, one can imagine that >>> when we would have bigger list than we can sort better and have more >>> file's requests at the same tape. >>> >>> Our framework gives a possibility that user's lists within one job are >>> already sorted in some fashion and with a big hope that those files are >>> presumably at the same tape. The problem is that processing of these >>> lists goes at subsequent order, one by one. >>> So, my effort is to give to xrootd a list of files to "prepared" before >>> processing them (or at least the full list would start to be prepared >>> when job will start). Can I somehow "publish" to server that these files >>> from the list, I will use in very close future ? >>> >>> So, I have figured 2 possible cases how to do it: >>> >>> 1) Use AsyncOpen at client side >>> >>> I am scared of this solution, since it can use lots of resources >>> with many simultaneously opened connections. I can see jobs with >>> thousand of files. In our case, when we have 400 nodes for job's >>> processing, it could be very big number of connections to redirector node. >>> >>> 2) There is some sort of "prepare" methods at server side. So, how can I >>> call them from the client side ? >>> >>> This solution would be better for me, if I could somehow pass the list >>> to the server through the client and do not need any other assistance or >>> presence of the client at each file's preparation. >>> I know that there could be a problem with this. The files can disappear >>> between the prepared and actual requested time of processing. (server >>> went down, purging etc.). I think that the occurrence of this case is >>> usually very small. However, I didn't make any sophisticated >>> investigation to prove it since it would be very hard to get these >>> statistic. >>> >>> Thanks for any suggestion or help >>> Cheers >>> Pavel >>>