Re: [zfs-discuss] Is there performance penalty when adding vdev to existing pool

2013-02-20 Thread Ian Collins
Peter Wood wrote: Currently the pool is about 20% full: # zpool list pool01 NAME SIZE ALLOC FREE EXPANDSZCAP DEDUP HEALTH ALTROOT pool01 65.2T 15.4T 49.9T -23% 1.00x ONLINE - # So you will be about 15% full after adding a new vdev. Unless you are likely to get

Re: [zfs-discuss] Is there performance penalty when adding vdev to existing pool

2013-02-20 Thread Peter Wood
Currently the pool is about 20% full: # zpool list pool01 NAME SIZE ALLOC FREE EXPANDSZCAP DEDUP HEALTH ALTROOT pool01 65.2T 15.4T 49.9T -23% 1.00x ONLINE - # The old data and new data will be equally use after adding the vdev. The FS hold tens of thousands of sma

Re: [zfs-discuss] Is there performance penalty when adding vdev to existing pool

2013-02-20 Thread Ian Collins
Bob Friesenhahn wrote: On Thu, 21 Feb 2013, Sašo Kiselkov wrote: On 02/21/2013 12:27 AM, Peter Wood wrote: Will adding another vdev hurt the performance? In general, the answer is: no. ZFS will try to balance writes to top-level vdevs in a fashion that assures even data distribution. If your

Re: [zfs-discuss] Is there performance penalty when adding vdev to existing pool

2013-02-20 Thread Tim Cook
On Wed, Feb 20, 2013 at 5:46 PM, Bob Friesenhahn < bfrie...@simple.dallas.tx.us> wrote: > On Thu, 21 Feb 2013, Sašo Kiselkov wrote: > > On 02/21/2013 12:27 AM, Peter Wood wrote: >> >>> Will adding another vdev hurt the performance? >>> >> >> In general, the answer is: no. ZFS will try to balance

Re: [zfs-discuss] Is there performance penalty when adding vdev to existing pool

2013-02-20 Thread Bob Friesenhahn
On Thu, 21 Feb 2013, Sašo Kiselkov wrote: On 02/21/2013 12:27 AM, Peter Wood wrote: Will adding another vdev hurt the performance? In general, the answer is: no. ZFS will try to balance writes to top-level vdevs in a fashion that assures even data distribution. If your data is equally likely

Re: [zfs-discuss] Is there performance penalty when adding vdev to existing pool

2013-02-20 Thread Sašo Kiselkov
On 02/21/2013 12:27 AM, Peter Wood wrote: > Will adding another vdev hurt the performance? In general, the answer is: no. ZFS will try to balance writes to top-level vdevs in a fashion that assures even data distribution. If your data is equally likely to be hit in all places, then you will not in

Re: [zfs-discuss] Is there performance penalty when adding vdev to existing pool

2013-02-20 Thread Ian Collins
Peter Wood wrote: I'm using OpenIndiana 151a7, zpool v28, zfs v5. When I bought my storage servers I intentionally left hdd slots available so I can add another vdev when needed and delay immediate expenses. After reading some posts on the mailing list I'm getting concerned about degrading

[zfs-discuss] Is there performance penalty when adding vdev to existing pool

2013-02-20 Thread Peter Wood
I'm using OpenIndiana 151a7, zpool v28, zfs v5. When I bought my storage servers I intentionally left hdd slots available so I can add another vdev when needed and delay immediate expenses. After reading some posts on the mailing list I'm getting concerned about degrading performance due to unequ