Issue #2863 has been updated by shamaz. File flusher_tid.patch added
OK, I get it now. As you said before hmp->flusher.tid > starts off with 0. > unless you have something to sync it's 0. So if you mount your filesystem and yet has nothing to sync, when you create a new snapshot, its transaction ID will be that of hmp->flusher.tid, that's zero. So if you want it to increase monotonically, you must initialize hmp->flusher.tid earlier. I wrote a patch, please tell me if it is OK. ---------------------------------------- Bug #2863: HAMMER synch tid is zero http://bugs.dragonflybsd.org/issues/2863#change-12771 * Author: shamaz * Status: New * Priority: Normal * Assignee: * Category: * Target version: ---------------------------------------- Hello. This appears on DragonFlyBSD 4.2 (and maybe newer) if you try the following with HAMMER filesystem: 1) Create a new vnode device. # dd if=/dev/zero of=test.img bs=1m count=15000 # vnconfig -c vn test.img # disklabel64 -w -r vn4s0 auto # disklabel64 -e vn4s0 Add a line like "a: * 0 HAMMER" 2) Create a HAMMER filesystem: newfs_hammer -f -L TEST /dev/vn4s0a 3) Mount it: mount /dev/vn4s0a /mnt 4) Try to sync it: hammer synctid /mnt You will see zero sync tid (0x0000000000000000). If you try to set some debug-related sysctls, it will get you no info at all when syncing. Also hammer pfs-status /mnt will show that sync-end-tid does not increment in time as it should. I am not sure if it happens with any non-root hammer FS, or just with those based on vn pseudo disks. ---Files-------------------------------- flusher_tid.patch (492 Bytes) -- You have received this notification because you have either subscribed to it, or are involved in it. To change your notification preferences, please click here: http://bugs.dragonflybsd.org/my/account
