The time has come to expand my OpenSolaris NAS. Right now I have 6 1TB Samsung Spinpoints in a Raidz2 configuration. I also have a mirrored root pool. The Raidz2 configuration should be for my most critical data - but right now it is holding everything so I need to add some more pools and move some data around. To start I need a vdev I will call "temp" that acts as a networked bit bucket for me to drop items I want to keep around for a while, but don''t really care if I lose any data in there. If I wont be using this in a raidz configuration, just a single drive vdev - can I use any 2TB drive? Even the WD that lie about their sector size? Speed is not really of any importance here. I also need another vdev to store my media backups. These are very large files that take up a lot of space. It would be a bummer if I lost data here, but all of the data is replaceable, it would just take time and effort. I am thinking of RaidZ1 for this data. Are there any 2TB drives that will work with ZFS presently? I am willing to take the risk that if I lost a single disk, that they others wouldn''t fail during the stress of a resilver. Write speed doesn''t matter to me. But I need read speeds to supply at least 40mbit/second. I have 8GB of ram on this machine with usually 1 sometimes 2 concurrent reads - so I think prefetch should take care of these read demands regardless if the drive is green. So my question for this vdec is.. What is the best 2TB drive available for a raidz1 configuration? Are the samsung F4s a valid option or should I be looking at the seagates? I have pretty much written off the WD due to the 4k/512 byte sector nonsense. -- This message posted from opensolaris.org
> can I use any 2TB drive? ?Even the WD that lie about their sector size? ?Speed is not really of any importance here.Yes, you can. The WD will lie and say it''s 512-byte sectors, and you''ll get misaligned reads/writes and performance will suffer but it will work.> I also need another vdev to store my media backups. ?These are very large files that take up a lot of space. ?It would be a bummer if I lost data here, but all of the data is replaceable, it would just take time and effort. ?I am thinking of RaidZ1 for this data. ?Are there any 2TB drives that will work with ZFS presently? ?I am willing to take the risk that if I lost a single disk, that they others wouldn''t fail during the stress of a resilver. ?Write speed doesn''t matter to me. ?But I need read speeds to supply at least 40mbit/second. ?I have 8GB of ram on this machine with usually 1 sometimes 2 concurrent reads - so I think prefetch should take care of these read demands regardless if the drive is green. ?So my question for this vdec is.. What is the best 2TB drive available for a raidz1 configuration? ?Are the samsung F4s a valid option or should I be looking at the seagates? ?I have pretty much written off the WD due to the 4k/512 byte sector nonsense.The Hitachi 7K2000s are THE most foolproof, because they are pure 512-byte sector drives. No ifs, thens or buts. Seagates (at least the Barracuda LPs) utilize a tech called ''SmartAlign''; apparently it performs pretty well (taemun on the list has used both those drives and F4s). The F4s are 4K-sector drives as well, and I''m relatively certain they do some emulation goofiness. Safest option: 7K2000. Hopefully by the time you need to expand again, whether a drive is 4K or not should not matter anymore when it comes to ZFS.
----- Original Message -----> The time has come to expand my OpenSolaris NAS. > > Right now I have 6 1TB Samsung Spinpoints in a Raidz2 configuration. I > also have a mirrored root pool. > > The Raidz2 configuration should be for my most critical data - but > right now it is holding everything so I need to add some more pools > and move some data around.Just a quick question - have you considered using autoexpand here? Replacing each of the 1TB Drives with 2TB drives and waiting for the pool to resilver means you''ll be going from a 4TB pool to a 8TB pool with no downtime whatsoever (given you can hotswap). Vennlige hilsener / Best regards roy -- Roy Sigurd Karlsbakk (+47) 97542685 roy at karlsbakk.net http://blogg.karlsbakk.net/ -- I all pedagogikk er det essensielt at pensum presenteres intelligibelt. Det er et element?rt imperativ for alle pedagoger ? unng? eksessiv anvendelse av idiomer med fremmed opprinnelse. I de fleste tilfeller eksisterer adekvate og relevante synonymer p? norsk.
Thanks. I hadn''t come across the Hitachi''s They certainly seem to have a price premium associated with them - but I suppose that is to be expected. I was sort of looking towards ''greener'' drives since performance wasn''t a large factor for either of these vdevs. Seems too bad all the others do some form of emulation without any options to turn them off. I may look at a Seagate LP for my temp dev - as that will hold me over for a while until there is a price drop or a sale on the Hitachi disks. -- This message posted from opensolaris.org
I had not really considered that. I was going under the assumption that 2TB drives are still "too big" for a single vdev in terms of resilver times if there is a failure. I also have a 20 bay case, so I have plenty of room to expand. So I wold keep my 1TB drives around anyhow. Thanks for the suggestion! -- This message posted from opensolaris.org
On 12/10/2010 7:07 PM, Brian wrote:> I had not really considered that. I was going under the assumption that 2TB drives are still "too big" for a single vdev in terms of resilver times if there is a failure. I also have a 20 bay case, so I have plenty of room to expand. So I wold keep my 1TB drives around anyhow. > > Thanks for the suggestion!Resilver times are going to be heavily influenced by the number of files you store (in addition to mirror vs raidzN). Obviously, a 2TB drive can store 2x the number of files a 1TB would. If the vast majority of files on the raidz are going to be large in size, then you won''t see too much of a penalty for using 2TB vs 1TB. -- Erik Trimble Java System Support Mailstop: usca22-123 Phone: x17195 Santa Clara, CA Timezone: US/Pacific (GMT-0800)