First Post! Sorry, I had to get that out of the way to break the ice... I was wondering if it makes sense to zone ZFS pools by disk slice, and if it makes a difference with RAIDZ. As I'm sure we're all aware, the end of a drive is half as fast as the beginning ([i]where the zoning stipulates that the physical outside is the beginning and going towards the spindle increases hex value[/i]).
I usually short stroke my drives so that the variable files on the operating system drive are at the beginning, page in center (so if I'm already in thrashing I'm at most 1/2 a platters width from page), and static files are towards the end. So, applying this methodology to ZFS, I partition a drive into 4 equal-sized quarters, and do this to 4 drives (each on a separate SATA channel), and then create 4 pools which hold each 'ring' of the drives. Will I then have 4 RAIDZ pools, which I can mount according to speed needs? For instance, I always put (in Linux... I'm new to Solaris) '/export/archive' all the way on the slow tracks since I don't read or write to it often and it is almost never accessed at the same time as anything else that would force long strokes. Ideally, I'd like to do a straight ZFS on the archive track. I move data to archive in chunks, 4 gigs at a time - when I roll it in I burn 2 DVDs, 1 gets cataloged locally and the other offsite, so if I lose the data, I don't care - but, ZFS gives me the ability to snapshot to archive (I assume it works across pools?). Then stripe 1 ring (I guess this is ZFS native?), /usr/local (or its Solaris equivalent) for performance. Then mirror the root slice. Finally, /export would be RAIDZ or RAIDZ2 on the fastest track, holding my source code, large files, and things I want to stream over the LAN. Does this make sense with ZFS? Is the spindle count more of a factor than stroke latency? Does ZFS balance these things out on its own via random scattering? Reading back over this post, I've found it sounds like the ramblings of a madman. I guess I know what I want to say, but I'm not sure the right questions to ask. I think I'm saying: Will my proposed setup afford me the flexibility to zone for performance since I have a more intimate knowledge of the data going onto the drive, or will brute force by spindle count (I'm planning 4-6 drives - single drive to a bus) and random placement be sufficient if I just add the whole drive to a single pool? I thank you all for your time and patience as I stumble through this, and I welcome any point of view or insights (especially those from experience!) that might help me decide how to configure my storage server. This message posted from opensolaris.org _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
