The application I use, StoRM[1] can store checksums on disk in an extended user attribute - and use that to ensure the integrity of files on disk. The algorithm currently used is adler32. The intention is to perform end to end checksumming from file creation through storage, transfer over the WAN and storage at a site.
Looking at http://wiki.lustre.org/manual/LustreManual20_HTML/ManagingFileSystemIO.html#50438211_pgfId-1291975 I see that Lustre has some checksum support (though not for checksumming the file on the OST - so we'd still need to use the user attribute for that). http://wiki.lustre.org/manual/LustreManual18_HTML/LustreTuning.html#50651264_pgfId-1291287 Is the value of the checksum user accessible? Or to be more specific, I'd potentially get a big speedup if I were able to ask the diskserver to tell me the checksum of a file without actually transferring it over the network. Is it easy to do this? Chris [1] http://storm.forge.cnaf.infn.it/home This is an SRM implementation we use to give an grid authentication to our storage (we store data for the LHC). _______________________________________________ Lustre-discuss mailing list [email protected] http://lists.lustre.org/mailman/listinfo/lustre-discuss
