Re: [zfs-discuss] zfs-discuss Digest, Vol 56, Issue 126
On Jun 28, 2010, at 10:03 AM, zfs-discuss-requ...@opensolaris.org wrote: Send zfs-discuss mailing list submissions to zfs-discuss@opensolaris.org To subscribe or unsubscribe via the World Wide Web, visit http://mail.opensolaris.org/mailman/listinfo/zfs-discuss or, via email, send a message with subject or body 'help' to zfs-discuss-requ...@opensolaris.org You can reach the person managing the list at zfs-discuss-ow...@opensolaris.org When replying, please edit your Subject line so it is more specific than Re: Contents of zfs-discuss digest... Today's Topics: 1. Re: ZFS bug - should I be worried about this? (Gabriele Bulfon) 2. Re: ZFS bug - should I be worried about this? (Victor Latushkin) 3. Re: OCZ Vertex 2 Pro performance numbers (Frank Cusack) 4. Re: ZFS bug - should I be worried about this? (Garrett D'Amore) 5. Announce: zfsdump (Tristram Scott) 6. Re: Announce: zfsdump (Brian Kolaci) 7. Re: zpool import hangs indefinitely (retry post in parts; too long?) (Andrew Jones) 8. Re: Announce: zfsdump (Tristram Scott) 9. Re: Announce: zfsdump (Brian Kolaci) -- Message: 1 Date: Mon, 28 Jun 2010 05:16:00 PDT From: Gabriele Bulfon gbul...@sonicle.com To: zfs-discuss@opensolaris.org Subject: Re: [zfs-discuss] ZFS bug - should I be worried about this? Message-ID: 593812734.121277727391600.javamail.tweb...@sf-app1 Content-Type: text/plain; charset=UTF-8 Yes...they're still running...but being aware that a power failure causing an unexpected poweroff may make the pool unreadable is a pain Yes. Patches should be available. Or adoption may be lowering a lot... -- This message posted from opensolaris.org -- Message: 2 Date: Mon, 28 Jun 2010 18:14:12 +0400 From: Victor Latushkin victor.latush...@sun.com To: Gabriele Bulfon gbul...@sonicle.com Cc: zfs-discuss@opensolaris.org Subject: Re: [zfs-discuss] ZFS bug - should I be worried about this? Message-ID: 4c28ae34.1030...@sun.com Content-Type: text/plain; CHARSET=US-ASCII; format=flowed On 28.06.10 16:16, Gabriele Bulfon wrote: Yes...they're still running...but being aware that a power failure causing an unexpected poweroff may make the pool unreadable is a pain Pool integrity is not affected by this issue. -- Message: 3 Date: Mon, 28 Jun 2010 07:26:45 -0700 From: Frank Cusack frank+lists/z...@linetwo.net To: 'OpenSolaris ZFS discuss' zfs-discuss@opensolaris.org Subject: Re: [zfs-discuss] OCZ Vertex 2 Pro performance numbers Message-ID: 5f1b59775f3ffc0e1781f...@cusack.local Content-Type: text/plain; charset=us-ascii; format=flowed On 6/26/10 9:47 AM -0400 David Magda wrote: Crickey. Who's the genius who thinks of these URLs? SEOs -- Message: 4 Date: Mon, 28 Jun 2010 08:17:21 -0700 From: Garrett D'Amore garr...@nexenta.com To: Gabriele Bulfon gbul...@sonicle.com Cc: zfs-discuss@opensolaris.org Subject: Re: [zfs-discuss] ZFS bug - should I be worried about this? Message-ID: 1277738241.5596.4325.ca...@velocity Content-Type: text/plain; charset=UTF-8 On Mon, 2010-06-28 at 05:16 -0700, Gabriele Bulfon wrote: Yes...they're still running...but being aware that a power failure causing an unexpected poweroff may make the pool unreadable is a pain Yes. Patches should be available. Or adoption may be lowering a lot... I don't have access to the information, but if this problem is the same one I think it is, then the pool does not become unreadable. Rather, its state after such an event represents a *consistent* state from some point of time *earlier* than that confirmed fsync() (or a write on a file opened with O_SYNC or O_DSYNC). For most users, this is not a critical failing. For users using databases or requiring transactional integrity for data stored on ZFS, then yes, this is a very nasty problem indeed. I suspect that this is the problem I reported earlier in my blog (http://gdamore.blogspot.com) about certain kernels having O_SYNC and O_DSYNC problems. I can't confirm this though, because I don't have access to the SunSolve database to read the report. (This is something I'll have to check into fixing... it seems like my employer ought to have access to that information...) - Garrett -- Message: 5 Date: Mon, 28 Jun 2010 08:26:02 PDT From: Tristram Scott tristram.sc...@quantmodels.co.uk To: zfs-discuss@opensolaris.org Subject: [zfs-discuss] Announce: zfsdump Message-ID: 311835455.361277738793747.javamail.tweb...@sf-app1 Content-Type: text/plain; charset=UTF-8 For quite some time I have been using zfs send -R fsn...@snapname | dd of=/dev/rmt/1ln to make a tape backup of my zfs file system. A few weeks back the size of the file system grew to larger
Re: [zfs-discuss] Replaced drive in zpool, was fine, now degraded - ohno
I'm on snv 111b. I attempted to get smartmontools workings, but it doesn't seem to want to work as these are all sata drives. Have you tried using '-d sat,12' when using smartmontools? opensolaris.org/jive/thread.jspa?messageID=473727 -- This message posted from opensolaris.org ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] Fileserver help.
Hi all. Im pretty new to the whole OpenSolaris thing, i've been doing a bit of research but cant find anything on what i need. I am thinking of making myself a home file server running OpenSolaris with ZFS and utilizing Raid/Z I was wondering if there is anything i can get that will allow Windows Media Center based hardware (HTPC or XBOX 360) to stream from my new fileserver? Any help is appreciated and remember im new :) Message was edited by: cloudz If whatever you are streaming to will read CIFS (or NFS) shares, you're golden. Getting set up is literally one command. If you are looking for uPnP streaming, the easiest (an only thing I ever got to work) solution out there is PS3mediaserver. It says it has Xbox360 support. It depends on mplayer and ffmpeg which are both available in the blastwave community repository (or you can try building them from source if you want.) There are a couple howto's on getting TwonkyMedia and MediaTomb running under Solaris if you google for them. I never could get either one to compile, but I haven't tried it in quite some time. I've heard of people running uPnP servers from linux branded zones as well, so that might be an option for you. I have no experience whatsoever with that, so I can't tell you much else about it. Personally, I gave up on trying to stream to my PS3. That is mainly because I don't have ethernet run to it, and trying to stream any media over wireless-g, especially the HD stuff, is frustrating to say the least. I dropped $100 on an xtreamer media player, and it's great. Plays any format/container I can throw at it. Works real well for me. Good luck! Eric -- This message posted from opensolaris.org ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] ZFS RaidZ recommendation
You may be absolutely right. CPU clock frequency certainly has hit a wall at around 4GHz. However, this hasn't stopped CPUs from getting progressively faster. I know this is mixing apples and oranges, but my point is that no matter what limits or barriers computing technology hits, someone comes along and finds a way to engineer around it. I have no idea what storage technology will look like years from now, but I will be very surprised if the limitations you've listed have held back advances in storage devices. No idea what those devices will look like or how they'll work. If someone told me roughly 10 years ago that I would be using multi-core processors at the same clock speed as my Pentium 4, I would have probably scoffed at the idea. Here we are. I'm a drinker, not a prophet ;-) Like I said, I've built my system planning to upgrade with bigger capacity drives when I start running out of space rather then adding more drives. This is almost certainly unrealistic. I've always built my systems around planned upgradeability, but whenever it does come time for an upgrade, it never makes sense to do so. It's usually much more cost effective to just build a new system with newer and better technology. It should take me a long while to fill up 9TB, but there was a time when I thought a single gigabyte was a ridiculous amount of storage too. Eric On Apr 8, 2010, at 11:21 PM, Erik Trimble wrote: Eric Andersen wrote: I find Erik Trimble's statements regarding a 1 TB limit on drives to be a very bold statement. I don't have the knowledge or the inclination to argue the point, but I am betting that we will continue to see advances in storage technology on par with what we have seen in the past. If we still are capped out at 2TB as the limit for a physical device in 2 years, I solemnly pledge now that I will drink a six-pack of beer in his name. Again, I emphasize that this assumption is not based on any sort of knowledge other than past experience with the ever growing storage capacity of physical disks. Why thank you for recognizing my bold, God-like predictive powers. It comes from my obviously self-descriptive name, which means Powerful/Eternal Ruler wink Ahem. I'm not saying that hard drive manufacturers have (quite yet) hit their ability to increase storage densities - indeed, I do expect to see 4TB drives some time in the next couple of years. What I am saying is that it doesn't matter if areal densities continue to increase - we're at the point now with 1TB drives where the number of predictable hard error rates is just below the level which we can tolerate. That is, error rates (errors per X bits read/written) have dropped linearly over the past 3 decades, while densities are on a rather severe geometric increase, and data transfer rate is effectively stopped increasing at all. What this means is that while you can build a higher-capacity disk, the time you can effectively use it is dropping (i.e. before it experiences a non-recoverable error and has to be replaced), and the time that it takes to copy off all the data from drive to another one is increasing. If X = (time to use ) and Y = (time to copy off data), when X 2*Y, you're screwed. In fact, from an economic standpoint, when X 100 * Y, you're pretty much screwed. And 1TB drives are about the place where they can still just pass this test. 1.5TB drives and up aren't going to be able to pass it. Everything I've said applies not only to 3.5 drives, but to 2.5 drives. It's a problem with the basic winchester hard drive technology. We just get a bit more breathing space (maybe two technology cycles, which in the HD sector means about 3 years) with the 2.5 form factor. But even they are doomed shortly. I got a pack of Bud with your name on it. :-) -- Erik Trimble Java System Support Mailstop: usca22-123 Phone: x17195 Santa Clara, CA Timezone: US/Pacific (GMT-0800) ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] ZFS RaidZ recommendation
I am doing something very similar. I backup to external USB's, which I leave connected to the server for obviously days at a time ... zfs send followed by scrub. You might want to consider eSATA instead of USB. Just a suggestion. You should be able to go about 4x-6x faster than 27MB/s. I did strongly consider going with eSATA. What I really wanted to use was FireWire 800 as it is reasonably fast and the ability to daisy chain devices is very appealing, but some of the stuff I've read regarding the state of OpenSolaris FireWire drivers scared me off. I decided against eSATA because I don't have any eSATA ports. I could buy a controller or run SATA to eSATA cables of the four available onboard ports, but either way, when/if I run out of ports, that's it. With USB, I can always use a hub if needed (at even slower speeds). If OpenSolaris supported SATA port multipliers, I'd have definitely gone with eSATA. The speed issue isn't really critical to me, especially if I'm doing incremental send/receives. Recovering my data from backup will be a drag, but it is what it is. I decided cheap and simple was best, and went with USB. I have found external enclosures to be unreliable. For whatever reason, they commonly just flake out, and have to be power cycled. This is unfortunately disastrous to solaris/opensolaris. The machine crashes, you have to power cycle, boot up in failsafe mode, import the pool(s) and then reboot once normal. This is what I've overwhelmingly heard as well. Most people point to the controllers in the enclosures. If I could find a reasonable backup method that avoided external enclosures altogether, I would take that route. For cost and simplicity it's hard to beat externals. I am wondering, how long have you been doing what you're doing? Do you leave your drives connected all the time? Have you seen similar reliability issues? What external hardware are you using? Not long (1 week), so I'm just getting started. I don't leave the drives connected. Plug them in, do a backup, zpool export, unplug and throw in my safe. It's far from great, but it beats what I had before (nothing). I plan to do an incremental zfs send/receive every 2-4 weeks depending on how much new data I have. I can't attest to any sort of reliability as I've only been at it for a very short period of time. I am using 2TB WD Elements drives (cheap). This particular model (WDBAAU0020HBK-NESN) hasn't been on the market too terribly long. There is one review on Newegg of someone having issues with one from the start. It sucks, but I think the reality is that it's pretty much a crapshoot when it comes to reliability on external drives/enclosures. I started doing this on one system (via eSATA) about a year ago. It worked flawlessly for about 4 months before the disk started crashing. I started doing it on another system (via USB) about 6 months ago. It just started crashing a couple of weeks ago. I am now in the market to try and identify any *well made* external enclosures. The best I've seen so far is the Dell RD1000, but we're talking crazy overpriced, and hard drives that are too small to be useful to me. If you find something good, please let me know. There are a lot of different solutions for a lot of different scenarios and price points. I went with cheap. I won't be terribly surprised if these drives end up flaking out on me. You usually get what you pay for. What I have isn't great, but it's better than nothing. Hopefully, I'll never need to recover data from them. If they end up proving to be too unreliable, I'll have to look at other options. Eric If we still are capped out at 2TB as the limit for a physical device in 2 years, I solemnly pledge now that I will drink a six-pack of beer in his name. I solemnly pledge to do it anyway. And why wait? ;-) ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] ZFS RaidZ recommendation
I thought I might chime in with my thoughts and experiences. For starters, I am very new to both OpenSolaris and ZFS, so take anything I say with a grain of salt. I have a home media server / backup server very similar to what the OP is looking for. I am currently using 4 x 1TB and 4 x 2TB drives set up as mirrors. Tomorrow, I'm going to wipe my pool and go to 4 x 1TB and 4 x 2TB in two 4 disk raidz's. I backup my pool to 2 external 2TB drives that are simply striped using zfs send/receive followed by a scrub. As of right now, I only have 1.58TB of actual data. ZFS send over USB2.0 capped out at 27MB/s. The scrub for 1.5TB of backup data on the USB drives took roughly 14 hours. As needed, I'll destroy the backup pool and add more drives as needed. I looked at a lot of different options for external backup, and decided to go with cheap (USB). I am using 1TB and 2TB WD Caviar Green drives for my storage pool, which are about the cheapest and probably close to the slowest consumer drives you can buy. I've only been at this for about 4-5 months now, and thankfully I haven't had a drive fail yet so I cannot attest to resilver times. I do weekly scrubs on both my rpool and storage pool via a script called through cron. I just set things up to do scrubs during a timeframe when I know I'm not going to be using it for anything. I can't recall the exact times it took for the scrubs to complete, but it wasn't anything that interfered with my usage (yet...) The vast majority of any streaming media I do (up to 1080p) is over wireless-n. Occasionally, I will get stuttering (on the HD stuff), but I haven't looked into whether it was due to a network or I/O bottleneck. Personally, I would think it was due to network traffic, but that is pure speculation. The vast majority of the time, I don't have any issues whatsoever. The main point I'm trying to make is that I'm not I/O bound at this point. I'm also not streaming to 4 media players simultaneously. I currently have far more storage space than I am using. When I do end up running low on space, I plan to start with replacing the 1TB drives with, hopefully much cheaper at that point, 2TB drives. If using 2 x raidz vdevs doesn't work well for me, I'll go back to mirrors and start looking at other options for expansion. I find Erik Trimble's statements regarding a 1 TB limit on drives to be a very bold statement. I don't have the knowledge or the inclination to argue the point, but I am betting that we will continue to see advances in storage technology on par with what we have seen in the past. If we still are capped out at 2TB as the limit for a physical device in 2 years, I solemnly pledge now that I will drink a six-pack of beer in his name. Again, I emphasize that this assumption is not based on any sort of knowledge other than past experience with the ever growing storage capacity of physical disks. My personal advice to the OP would be to set up three 4 x 1TB raidz vdevs, and investing in a reasonable backup solution. If you have to use the last two drives, set them up as a mirror. Redundancy is great, but in my humble opinion, for the home user that is using cheap hardware, it's not as critical as performance and available storage space. That particular configuration would give you more IOPS than just two raidz2 vdevs, with slightly less redundancy and slightly more storage space. For my own needs, I don't see redundancy as being as high a priority as IOPS and available storage space. Everyone has to make their own decision on that, and the ability of ZFS to accommodate a vast array of different individual needs is a big part of what makes it such an excellent filesystem. With a solid backup, there is really no reason you can't redesign your pool at a later date if need be. Try out what you think will work best, and if that configuration doesn't work well in s ome way, adjust and move on... There are a few different schools of thought on how to backup ZFS filesystems. ZFS send/receive works for me, but there are certainly weaknesses with using it as a backup solution (as has been much discussed on this list.) Hopefully, in the future it will be possible to remove vdevs from a pool and to restripe data across a pool. Those particular features would certainly be great for me. Just my thoughts. Eric -- This message posted from opensolaris.org ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] RAID10
It depends a bit on how you set up the drives really. You could make one raidz vdev of 8 drives, losing one of them for parity, or you could make two raidz vdevs of 4 drives each and lose two drives for parity (one for each vdev). You could also do one raidz2 vdev of 8 drives and lose two drives for parity, or two raidz2 vdevs of 4 drives each and lose four drives for parity (2 for each raidz2 vdev). That would give you a bit better redundancy than using 4 mirrors while giving you the same available storage space. The list goes on and on. There are a lot of different configurations you could use with 8 drives, but keep in mind once you add a vdev to your pool, you can't remove it. Personally, I would not choose to create one vdev of 8 disks, but that's just me. It is important to be aware that when and if you want to replace the 1.5TB disks with something bigger, you need to replace ALL the disks in the vdev to gain the extra space. So, if you wanted to go from 1.5TB to 2TB disks down the road, and you set up one raidz of 8 drives, you need to replace all 8 drives before you gain the additional space. If you do two raidz vdevs of 4 drives each, you need to replace 4 drives to gain additional space. If you use mirrors, you need to replace 2 drives. Or, you can add a new vdev of 2, 4, 8, or however many disks you want if you have the physical space to do so. I believe you can mix and match mirror vdevs and raidz vdevs within a zpool, but I don't think it's recommended to do so. The ZFS best practices guide has a lot of good information in it if you have not read it yet (google). You might have less usable drive space using mirrors, but you will gain a bit of performance, and it's a bit easier to expand your zpool when the time comes. A raidz (1,2,3) can give you more usable space, and can give you better or worse redundancy depending on how you set it up. There is a lot to consider. I hope I didn't cloud things up for you any further or misinform you on something (I'm a newb too, so don't take my word alone on anything). Hell, if you wanted to, you could also do one 8-way mirror that would give you an ignorant amount of redundancy at the cost of 7 drives worth of usable space. It all boils down to personal choice. You have to determine how much usable space, redundancy, performance, and ease of replacing drives mean to you and go from there. ZFS will do pretty much any configuration to suit your needs. eric -- This message posted from opensolaris.org ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] Q : recommendations for zpool configuration
I went through this determination when setting up my pool. I decided to go with mirrors instead of raidz2 after considering the following: 1. Drive capacity in my box. At most, I can realistically cram 10 drives in my box and I am not interested in expanding outside of the box. I could go with 2.5 inch drives and fit a lot more, but I don't feel the necessity to do so. That being said, given the historic trend for mass storage drives to become cheaper over time, I have a feeling that I will be replacing drives to expand storage space long before the drives themselves start failing. The added redundancy of raidz2 is great, but I am betting that, barring a poorly manufactured drive, I will be replacing the drives with bigger drives before they have a chance to reach the end of their life. 2. Taking into account the above, it's a great deal easier on the pocket book to expand two drives at a time instead of four at a time. As bigger drives are always getting cheaper, I feel that I have a lot more flexibility with mirrors when it comes to expanding. If you have limitless physical space for drives, you might feel differently. 3. Mirrors are going to perform better than raidz. Again, redundancy is great, but so is performance. My setup is for home use. I want to keep my data safe but at the same time I am limited by cost and space. I think that given the tradeoff between the two, mirrors win. I feel that the chances of two drives in a mirror failing simultaneously are remote enough that I'll take the risk. 4. Again, I'm running this at home. It's not mission critical to me to have my data available 24/7. Redundancy is a convenience and not a necessity. Regardless of what you choose, backups are what will save your ass in the event of catastrophe. Having said that, I currently don't have a good backup solution and how to implement a good backup solution seems to be a hot topic on this list lately. Figuring out how to easily, effectively and cheaply back up multiple terabytes of storage is my number one priority at the moment. So anyways, all things considered, I prefer the better performance and easier expansion of storage space vs my physical space over a relatively small layer of extra redundancy. If you aren't doing anything that necessitates the added redundancy of raidz2, go with mirrors. Either way, if you care about your data, back it up. eric -- This message posted from opensolaris.org ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
