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One for the inode >>> number, and the other to store the device major:minor number. Now the >>> output looks like this: >> >> WTF? Why are you back in the 1960's? What's next? The index into the >> paper card deck? >> >> Stop using inode numbers and device numbers already. It's the 21st >> century. No, cars still don't fly, but dammit, inode numbers were a >> great idea back in the days, but they are not acceptable any more. >> >> They *particularly* aren't acceptable when you apparently think that >> they are 'unsigned long'. Yes, that's the internal representation we >> use for inode indexing, but for example on nfs the inode is actually >> bigger. It's exposed to user space as a u64 through >> >> stat->ino = nfs_compat_user_ino64(NFS_FILEID(inode)); >> >> so the inode that user space sees in 'struct stat' (a) doesn't >> actually match inode->i_ino, and (b) isn't even the full file ID that >> NFS actually uses. >> >> Let's not let that 60's thinking be any part of a new interface. >> >> Give the damn thing an actual filename or something *useful*, not a >> number that user space can't even necessarily match up to anything. >> > > A build ID? > > PERF_RECORD_MMAP went thru this, filename -> inode -> Content based hash FWIW, we record: - executable or shared library path name, - build id (if available), - debug link (if available), in LTTng-UST when we dump the loaded executable and libraries from userspace. Thanks, Mathieu -- Mathieu Desnoyers EfficiOS Inc. https://www.efficios.com