similar to: jbod questions

1. I have a 4x18GB drive setup as RAIDZ. Now when thinking about it in terms of RAID5 I would expect to get (4-1)x18 worth of drive space, but DF -h shows 4x18. Is this a bug or do I not understand? 2. Once again thinking in RAID5 terms if I have 4X18GB and 12X9GB drives and I want to make a RAIDZ of all of them I would expect the 18GB to be treated at 9GB so the RAIDZ would be 16X9GB. Is

"Does raidzN actually protect against bitrot?" That''s a kind of radical, possibly offensive, question formula that I have lately. Reading up on theory of RAID5, I grasped the idea of the write hole (where one of the sectors of the stripe, such as the parity data, doesn''t get written - leading to invalid data upon read). In general, I think the same applies to bitrot of

The default blocksize is 128K. If you are using mirrors, then each block on disk will be 128K whenever possible. But if you''re using raidzN with a capacity of M disks (M disks useful capacity + N disks redundancy) then the block size on each individual disk will be 128K / M. Right? This is one of the reasons the raidzN resilver code is inefficient. Since you end up waiting for the

hi all, I am hoping to move roughly 1TB of maildir format email to ZFS, but I am unsure of what the most appropriate disk configuration on a 3510 would be. based on the desired level of redundancy and usable space, my thought was to create a pool consisting of 2x RAID-Z vdevs (either double parity, or single parity with two hot-spares). using 300GB drives this would give roughly 2.4TB of usable

Given a 1.6TB ZFS Z-Raid consisting 6 disks: And a system that does an extreme amount of small /(<20K) /random reads /(more than twice as many reads as writes) / 1) What performance gains, if any does Z-Raid offer over other RAID or Large filesystem configurations? 2) What is any hindrance is Z-Raid to this configuration, given the complete randomness and size of these accesses? Would

Hello, I have a Dell 2950 with a Perc 5/i, two 300GB 15K SAS drives in a RAID0 array. I am considering going to ZFS and I would like to get some feedback about which situation would yield the highest performance: using the Perc 5/i to provide a hardware RAID0 that is presented as a single volume to OpenSolaris, or using the drives separately and creating the RAID0 with OpenSolaris and ZFS? Or

Dear all, we''re currently looking forward to restructure our hardware environment for our datawarehousing product/suite/solution/whatever. We''re currently running the database side on various SF V440''s attached via dual FC to our SAN backend (EMC DMX3) with UFS. The storage system is (obviously in a SAN) shared between many systems. Performance is mediocre in terms

Hi all :) I''ve been wanting to make the switch from XFS over RAID5 to ZFS/RAIDZ2 for some time now, ever since I read about ZFS the first time. Absolutely amazing beast! I''ve built my own little hobby server at home and have a boatload of disks in different sizes that I''ve been using together to build a RAID5 array on Linux using mdadm in two layers; first layer is

Hi, for zfs raidz1, I know for random io, iops of a raidz1 vdev eqaul to one physical disk iops, since raidz1 is like raid5 , so is raid5 has same performance like raidz1? ie. random iops equal to one physical disk''s ipos. Regards Victor -- This message posted from opensolaris.org

Hi there Is it fair to compare the 2 solutions using Solaris 10 U2 and a commercial database (SAP SD scenario). The cache on the HW raid helps, and the CPU load is less... but the solution costs more and you _might_ not need the performance of the HW RAID. Has anybody with access to these units done a benchmark comparing the performance (and with the pricelist in hand) came to a conclusion.

I'm trying to improve the setup of our Dovecot/Exim mail servers to handle the increasingly huge accounts (everybody thinks it's like infinitely growing storage like gmail and stores everything forever in their email accounts) by changing from Maildir to mdbox, and to take advantage of offloading older emails to alternative networked storage nodes. The question now is whether having a

I cannot verify it, but I think that even JBOD is propagated as a virtual device. If you create JBOD from 3 different disks, low level parameters may differ. And probably old firmware is the reason we used RAID-0 two or three years before. Thank you for the ideas. Kind regards Milo Dne 10.09.2020 v 16:15 Scott Q. napsal(a): > Actually there is, filesystems like ZFS/BTRFS prefer to see

Just posted: http://blogs.sun.com/roch/entry/nfs_and_zfs_a_fine ____________________________________________________________________________________ Performance, Availability & Architecture Engineering Roch Bourbonnais Sun Microsystems, Icnc-Grenoble Senior Performance Analyst 180, Avenue De L''Europe, 38330, Montbonnot Saint

Hi All, I am looking at ZFS and I get that they call it RAIDZ which is similar to RAID 5, but what about RAID 10? Isn''t a RAID 10 setup better for data protection? So if I have 8 x 1.5tb drives, wouldn''t I: - mirror drive 1 and 5 - mirror drive 2 and 6 - mirror drive 3 and 7 - mirror drive 4 and 8 Then stripe 1,2,3,4 Then stripe 5,6,7,8 How does one do this with ZFS?

As mentioned last night, we''ve been reviewing a proposal for hot spare support in ZFS. Below you can find a current draft of the proposed interfaces. This has not yet been submitted for ARC review, but comments are welcome. Note that this does not include any enhanced FMA diagnosis to determine when a device is "faulted". This will come in a follow-on project, of which some

I''m putting together a NexentaOS (b65)-based server that has 4 500 GB drives on it. Currently it has two, set up as a ZFS mirror. I''m able to boot Nexenta from it, and it seems to work ok. But, as I''ve learned, the mirror is not properly redundant, and so I can''t just have a drive fail (when I pull one, the OS ends up hanging, and even if I replace it, I have to

Hi. I''m managing a HDS storage system which is slightly larger than 100 TB and we have used approx. 3/4. We use vxfs. The storage system is attached to a solaris 9 on sparc via a fiberswitch. The storage is shared via nfs to our webservers. If I was to replace vxfs with zfs I could utilize raidz(2) instead of the built-in hardware raid-controller. Are there any jbod-only storage

The time has come to review the current Contributor and Core contributor grants for ZFS. Since all of the ZFS core contributors grants are set to expire on 02-24-2009 we need to renew the members that are still contributing at core contributor levels. We should also add some new members to both Contributor and Core contributor levels. First the current list of Core contributors: Bill

I''ve got 12Gb or so of db+web in a zone on a ZFS filesystem on a mirrored zpool. Noticed during some performance testing today that its i/o bound but using hardly any CPU, so I thought turning on compression would be a quick win. I know I''ll have to copy files for existing data to be compressed, so I was going to make a new filesystem, enable compression and rysnc everything in,

I''m new so opensolaris and very new to ZFS. In the past we have always used linux for our database backends. So now we are looking for a new database server to give us a big performance boost, and also the possibility for scalability. Our current database consists mainly of a huge table containing about 230 million records and a few (relatively) smaller tables (something like 13 million