Re: [zfs-discuss] Is ZFS file system supports short writes ?
If a write call attempted to write X bytes of data, and if writecall writes only x ( hwere x X) bytes, then we call that write as short write. -Masthan Torrey McMahon [EMAIL PROTECTED] wrote: Robert Milkowski wrote: Hello dudekula, Thursday, February 15, 2007, 11:08:26 AM, you wrote: Hi all, Please let me know the ZFS support for short writes ? And what are short writes? http://www.pittstate.edu/wac/newwlassignments.html#ShortWrites :-P - Food fight? Enjoy some healthy debate in the Yahoo! Answers Food Drink QA.___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
[zfs-discuss] ZFS with SAN Disks and mutipathing
Hi, I just deploy the ZFS on an SAN attach disk array and it's working fine. How do i get dual pathing advantage of the disk ( like DMP in Veritas). Can someone point to correct doc and setup. Thanks in Advance. Rgds Vikash Gupta 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 with SAN Disks and mutipathing
http://docs.sun.com/source/819-0139/index.html On 2/17/07, Vikash Gupta [EMAIL PROTECTED] wrote: Hi, I just deploy the ZFS on an SAN attach disk array and it's working fine. How do i get dual pathing advantage of the disk ( like DMP in Veritas). Can someone point to correct doc and setup. Thanks in Advance. Rgds Vikash Gupta This message posted from opensolaris.org ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
[zfs-discuss] Zfs best practice for 2U SATA iSCSI NAS
Is there a best practice guide for using zfs as a basic rackable small storage solution? I'm considering zfs with a 2U 12 disk Xeon based server system vs something like a second hand FAS250. Target enviroment is mixature of Xen or VI hosts via iSCSI and nfs/cifs. Being able to take snapshots of running (or maybe paused) xen iscsi vols and re-export then for cloning and remote backup replication is important. the aspect I like about zfs is the offsite storage system can also be generic hardware and thus much cheaper. Being able to run a postgresql or mysql directly on the storage server has was postives as well, although a generic storage appliance has a better admin profile. Some questions: 1. how stable is zfs? i'm tolarent to some sweat work to fix problems but data loss is unacceptable 2. If drives need to be pulled and put into a new chasis does zfs handle them having new device names and being out of order? 3. Is it possible to hot swap drives with raidz(2) 4. How does performance compare with 'brand name' storage systems? Thanks Nicholas ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] Zfs best practice for 2U SATA iSCSI NAS
Hi Nicholas, ZFS itself is very stable and very effective as fast FS in our experience. If you browse the archives of the list you'll see that NFS performance is pretty acceptable, with some performance/RAM quirks around small files: http://www.opensolaris.org/jive/message.jspa?threadID=19858 http://www.opensolaris.org/jive/thread.jspa?threadID=18394 To my understanding the iSCSI driver is undergoing significant performance improvements...maybe someone close to this can help? If by VI you are referring to VMware Infrastructure...you won't get any support from VMware if you're using the iSCSI target on Solaris as its not approved by them. Not that this is really a problem in my experience as VMware tech support is pretty terrible anyway. Some questions: 1. how stable is zfs? i'm tolarent to some sweat work to fix problems but data loss is unacceptable We haven't experienced any data loss, and have had some pretty nasty things thrown at it (FC array rebooted unexpectedly). 2. If drives need to be pulled and put into a new chasis does zfs handle them having new device names and being out of order? My understanding and experience here is yes. It'll read the ZFS lables off the drives/slice. 3. Is it possible to hot swap drives with raidz(2) Depends on your underlying hardware. To my knowledge hot-swapping is not dependent on the RAID-level at all. 4. How does performance compare with 'brand name' storage systems? No clue if you're referring to NetApp. Does anyone else know? -J ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
[zfs-discuss] Google paper on disk reliability
Hi Folks I believe that the word would have gone around already, Google engineers have published a paper on disk reliability. It might supplement the ZFS FMA integration and well - all the numerous debates on spares etc etc over here. To quote /. The Google engineers just published a paper on Failure Trends in a Large Disk Drive Population. Based on a study of 100,000 disk drives over 5 years they find some interesting stuff. To quote from the abstract: 'Our analysis identifies several parameters from the drive's self monitoring facility (SMART) that correlate highly with failures. Despite this high correlation, we conclude that models based on SMART parameters alone are unlikely to be useful for predicting individual drive failures. Surprisingly, we found that temperature and activity levels were much less correlated with drive failures than previously reported.' Link to the paper is http://labs.google.com/papers/disk_failures.pdf This message posted from opensolaris.org ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
[zfs-discuss] Re: ZFS with SAN Disks and mutipathing
I'm using ZFS on both EMC and Pillar arrays with PowerPath and MPxIO, respectively. Both work fine - the only caveat is to drop your sd_queue to around 20 or so, otherwise you can run into an ugly display of bus resets. This message posted from opensolaris.org ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
