Re: geom <-> cam disk

2012-07-25 Thread Steven Hartland
- Original Message - From: "Andriy Gapon" on 26/07/2012 01:08 Alexander Motin said the following: Different controllers have different command queueing limitations. If you are testing with ahci(4) driver and modern disks, then their 32 command slots per port can be enough for many wor

Re: geom <-> cam disk

2012-07-25 Thread Warner Losh
On Jul 25, 2012, at 4:29 PM, Andriy Gapon wrote: > BTW, I think that it would be nice if the GEOM work-processing could re-use > the > CAM model. > That is, try to execute GEOM bio transformations in the original thread as > much > as possible, defer work to the GEOM thread as the last resort.

Re: geom <-> cam disk

2012-07-25 Thread Andriy Gapon
on 26/07/2012 01:08 Alexander Motin said the following: > Different controllers have different command queueing limitations. If you are > testing with ahci(4) driver and modern disks, then their 32 command slots per > port can be enough for many workloads to enqueue all commands to the hardware > a

Re: geom <-> cam disk

2012-07-25 Thread Andriy Gapon
. > On Jul 25, 2012, at 1:27 PM, Andriy Gapon wrote: > >> >> >> Preamble. I am trying to understand in detail how things work at GEOM <-> >> "CAM disk" boundary. I am looking at scsi_da and ata_da which seem to be >> twins in this respect. >&g

Re: geom <-> cam disk

2012-07-25 Thread Scott Long
from actually happening, though that's a topic that needs to be revisited. Scott On Jul 25, 2012, at 1:27 PM, Andriy Gapon wrote: > > > Preamble. I am trying to understand in detail how things work at GEOM <-> > "CAM > disk" boundary. I am looking at scsi_da an

Re: geom <-> cam disk

2012-07-25 Thread Alexander Motin
On 25.07.2012 23:27, Andriy Gapon wrote: Preamble. I am trying to understand in detail how things work at GEOM <-> "CAM disk" boundary. I am looking at scsi_da and ata_da which seem to be twins in this respect. I got an impression that the bioq_disksort calls in the strategy

geom <-> cam disk

2012-07-25 Thread Andriy Gapon
Preamble. I am trying to understand in detail how things work at GEOM <-> "CAM disk" boundary. I am looking at scsi_da and ata_da which seem to be twins in this respect. I got an impression that the bioq_disksort calls in the strategy methods and the related queues are compl