After around four days the process appeared to have stalled (no audible hard drive activity). I restarted with milestone=none; deleted /etc/zfs/zpool.cache, restarted, and went zpool import tank. (also allowed root login to ssh, so I could make new ssh sessions if required.) Now I can watch the process from on the machine.
My present question is how is the DDT stored? I believe the DDT to have around 10M entries for this dataset, as per: DDT-sha256-zap-duplicate: 400478 entries, size 490 on disk, 295 in core DDT-sha256-zap-unique: 10965661 entries, size 381 on disk, 187 in core (taken just previous to the attempt to destroy the dataset) A sample from iopattern shows: %RAN %SEQ COUNT MIN MAX AVG KR 100 0 195 512 512 512 97 100 0 414 512 65536 895 362 100 0 261 512 512 512 130 100 0 273 512 512 512 136 100 0 247 512 512 512 123 100 0 297 512 512 512 148 100 0 292 512 512 512 146 100 0 250 512 512 512 125 100 0 274 512 512 512 137 100 0 302 512 512 512 151 100 0 294 512 512 512 147 100 0 308 512 512 512 154 98 2 286 512 512 512 143 100 0 270 512 512 512 135 100 0 390 512 512 512 195 100 0 269 512 512 512 134 100 0 251 512 512 512 125 100 0 254 512 512 512 127 100 0 265 512 512 512 132 100 0 283 512 512 512 141 As the pool is comprised of 2x 8-disk raidz vdevs, I presume that each element is stored twice (for the raidz redundancy). So around 280 512b read op/s, that's 140 entries per second. Is the import of a semi-broken pool: 1> Reading all the DDT markers for the dataset; or 2> Reading all the DDT markers for the pool; or 3> Reading all of the block markers for the dataset; or 4> Reading all of the block markers for the pool Prior to actually finalising what it needs to do to fix the pool? I'd like to be able to estimate the length of time likely before the import finishes. Or should I tell it to roll back to the last valid txg - ie before the zfs destroy <dataset> command was issued? (by zpool import -F.) Or is this likely to take as long/longer than the present import/fix? Cheers. _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
