thanks for the reply. On 5/10/07, Al Hopper <[EMAIL PROTECTED]> wrote:
My personal opinion is that USB is not robust enough under (Open)Solaris to provide the reliability that someone considering ZFS is looking for. I base this on experience with two 7 port powered USB hubs, each with 4 * 2Gb Kingston flash drives, connected via 2 ports to a Solaris (update 3) desktop box which runs ZFS on two internal 500Gb drives. I see about 24 to 28Mb/Sec (bytes) maximum of bandwidth over each USB bus. One time, after disconnecting one hub (to show someone the hub with 4*USB drives) it hung the OS and reset the box. A subsequent import of the ZFS volume that was disconnected, failed. (Yes it was exported, but failed to import). So my take on USB is ... it's not sufficiently robust - and a USB related failure is likely to cause loss of the entire ZFS dataset; i.e., its likely to trash more that one drive in a raidz config.
this is exactly the kind of feedback i was hoping for. i'm wondering if some people consider firewire to be better in opensolaris? my goal is not for hot-pluggable storage; i'm fine with taking the machine down to replace drives, etc. i don't intend on disconnecting the USB cables or powering off the enclosure on purpose - but of course random unplanned events can happen, which is one of the reasons i want to use ZFS to begin with :)
I'd be interested in hearing other opinions on USB connected drives under (Open)Solaris ....
me too!
Suggestion - try two 4-way raidz pools.
wouldn't that bring usable space down to 2 pairs of 3x750? can those be combined into a single filesystem (for a total of 6x750 usable, but underlying would actually be the equivalent of 2 4x750 raid5 setups) why would you suggest this? would it improve some performance rather than having a raid-z2 on the 8 disks instead? thanks again! _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
