Re: btrfs raid multiple devices IO utilisation

2013-12-13 Thread Chris Murphy
On Dec 12, 2013, at 6:39 AM, Martin wrote: > Some time back, I noticed that with a two HDD btrfs raid1, some tasks > suffered ALL the IO getting choked onto just one HDD! > > > That turned out to be a feature of the btrfs code whereby a device is > chosen depending on the process ID. I wonder

Re: btrfs raid multiple devices IO utilisation

2013-12-13 Thread Martin
On 13/12/13 09:13, Duncan wrote: > Martin posted on Thu, 12 Dec 2013 13:39:00 + as excerpted: > >> Some time back, I noticed that with a two HDD btrfs raid1, some tasks >> suffered ALL the IO getting choked onto just one HDD! >> >> That turned out to be a feature of the btrfs code whereby a de

Re: btrfs raid multiple devices IO utilisation

2013-12-13 Thread Duncan
Martin posted on Thu, 12 Dec 2013 13:39:00 + as excerpted: > Some time back, I noticed that with a two HDD btrfs raid1, some tasks > suffered ALL the IO getting choked onto just one HDD! > > That turned out to be a feature of the btrfs code whereby a device is > chosen depending on the proces

btrfs raid multiple devices IO utilisation

2013-12-12 Thread Martin
Some time back, I noticed that with a two HDD btrfs raid1, some tasks suffered ALL the IO getting choked onto just one HDD! That turned out to be a feature of the btrfs code whereby a device is chosen depending on the process ID. For some cases such as in a bash loop, the PID increments by two fo