Our setup: - E2900 (24 x 96); Solaris 10 Update 2 (aka 06/06) - 2 2Gbps FC HBA - EMC DMX storage - 50 x 64GB LUNs configured in 1 ZFS pool - Many filesystems created with COMPRESS enabled; specifically I've one that is 768GB
I'm observing the following puzzling behavior: - We are currently creating a large (>1.4TB) and sparse dataset; most of the dataset contains repeating blanks (default/standard SAS dataset behavior.) - ls -l reports the file size as 1.4+TB and du -sk reports the actual on disk usage at around 65GB. - My I/O on the system is pegged at 150+MB/S as reported by zpool iostat and I've confirmed the same with iostat. This is very confusing - ZFS is doing very good compression as reported by the ratio of on disk versus as reported size of the file (1.4TB vs 65GB) - [b]Why on God's green earth am I observing such high I/O when indeed ZFS is compressing?[/b] I can't believe that the program is actually generating I/O at the rate of (150MB/S * compressratio). Any thoughts? This message posted from opensolaris.org _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
