Re: raid1 inefficient unbalanced filesystem reads

2013-06-29 Thread Russell Coker
On Sat, 29 Jun 2013, Martin m_bt...@ml1.co.uk wrote: Mmmm... I'm not sure trying to balance historical read/write counts is the way to go... What happens for the use case of an SSD paired up with a HDD? (For example an SSD and a similarly sized Raptor or enterprise SCSI?...) Or even just JBODs

Re: raid1 inefficient unbalanced filesystem reads

2013-06-29 Thread Martin
On 29/06/13 10:41, Russell Coker wrote: On Sat, 29 Jun 2013, Martin wrote: Mmmm... I'm not sure trying to balance historical read/write counts is the way to go... What happens for the use case of an SSD paired up with a HDD? (For example an SSD and a similarly sized Raptor or enterprise

raid1 inefficient unbalanced filesystem reads

2013-06-28 Thread Martin
On kernel 3.8.13: Using two equal performance SATAII HDDs, formatted for btrfs raid1 for both data and metadata and: The second disk appears to suffer about x8 the read activity of the first disk. This causes the second disk to quickly get maxed out whilst the first disk remains almost idle.

Re: raid1 inefficient unbalanced filesystem reads

2013-06-28 Thread Josef Bacik
On Fri, Jun 28, 2013 at 02:59:45PM +0100, Martin wrote: On kernel 3.8.13: Using two equal performance SATAII HDDs, formatted for btrfs raid1 for both data and metadata and: The second disk appears to suffer about x8 the read activity of the first disk. This causes the second disk to

Re: raid1 inefficient unbalanced filesystem reads

2013-06-28 Thread Hugo Mills
On Fri, Jun 28, 2013 at 11:34:18AM -0400, Josef Bacik wrote: On Fri, Jun 28, 2013 at 02:59:45PM +0100, Martin wrote: On kernel 3.8.13: Using two equal performance SATAII HDDs, formatted for btrfs raid1 for both data and metadata and: The second disk appears to suffer about x8 the

Re: raid1 inefficient unbalanced filesystem reads

2013-06-28 Thread Duncan
Hugo Mills posted on Fri, 28 Jun 2013 16:39:10 +0100 as excerpted: On Fri, Jun 28, 2013 at 11:34:18AM -0400, Josef Bacik wrote: On Fri, Jun 28, 2013 at 02:59:45PM +0100, Martin wrote: On kernel 3.8.13: Using two equal performance SATAII HDDs, formatted for btrfs raid1 for both data and

Re: raid1 inefficient unbalanced filesystem reads

2013-06-28 Thread Martin
On 28/06/13 16:39, Hugo Mills wrote: On Fri, Jun 28, 2013 at 11:34:18AM -0400, Josef Bacik wrote: On Fri, Jun 28, 2013 at 02:59:45PM +0100, Martin wrote: On kernel 3.8.13: Using two equal performance SATAII HDDs, formatted for btrfs raid1 for both data and metadata and: The second disk

Re: raid1 inefficient unbalanced filesystem reads

2013-06-28 Thread George Mitchell
On 06/28/2013 09:25 AM, Martin wrote: On 28/06/13 16:39, Hugo Mills wrote: On Fri, Jun 28, 2013 at 11:34:18AM -0400, Josef Bacik wrote: On Fri, Jun 28, 2013 at 02:59:45PM +0100, Martin wrote: On kernel 3.8.13: Using two equal performance SATAII HDDs, formatted for btrfs raid1 for both data

Re: raid1 inefficient unbalanced filesystem reads

2013-06-28 Thread Josef Bacik
On Fri, Jun 28, 2013 at 09:55:31AM -0700, George Mitchell wrote: On 06/28/2013 09:25 AM, Martin wrote: On 28/06/13 16:39, Hugo Mills wrote: On Fri, Jun 28, 2013 at 11:34:18AM -0400, Josef Bacik wrote: On Fri, Jun 28, 2013 at 02:59:45PM +0100, Martin wrote: On kernel 3.8.13: Using two equal

Re: raid1 inefficient unbalanced filesystem reads

2013-06-28 Thread Martin
On 28/06/13 18:04, Josef Bacik wrote: On Fri, Jun 28, 2013 at 09:55:31AM -0700, George Mitchell wrote: On 06/28/2013 09:25 AM, Martin wrote: On 28/06/13 16:39, Hugo Mills wrote: On Fri, Jun 28, 2013 at 11:34:18AM -0400, Josef Bacik wrote: On Fri, Jun 28, 2013 at 02:59:45PM +0100, Martin