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Yep, I am sorry, the executable is "xrd" in the bin directory... :-) Fabrizio Artem Trunov wrote: > Hi,Fabrizio! > > thanks, but sorry - what's the tool? :( > > Artem. > > On Thu, 26 Oct 2006, Fabrizio Furano wrote: > >> 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 >>>>>