Is there any limit on the number of snapshots in a file system? The documentation -- manual page, admin guide, troubleshooting guide -- does not mention any. That seems to confirm my assumption that is is probably not a fixed limit, but there may still be a practical one, just like there is no limit on the number of file systems in a pool, but nobody would find having a million file systems practical.
I have tried to create a number of snapshots in a file system for a few hours. An otherwise unloaded X4250 with a nearly empty RAID-Z2 pool of six builtin disks (146 GB, 10K rpm) managed to create a few snapshots per second in an empty file system. It had not visibly slowed down when it reached 36051 snapshots after hours and I stopped it; to my surprise destroying the file system (with all these snapshots in it) took about as long. With ``iostat -xn 1'' I could see that the disk usage was still low, at about 13% IIRC. So 36000 snapshots in an empty file system is not a problem. Is it different with a file system that is, say, to 70% full? Or on a bigger pool? Or with a significantly larger number of snapshots, say, a million? I am asking for real experience here, not for the theory. Regards, Juergen. _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
