Peter HEINER
2014-Dec-22 14:09 UTC
10.1 RC4 r273903 - zpool scrub on ssd mirror - ahci command timeout
> So I now think the whole problem centers around the Samsung 850 PRO > 512GB SSDs. Too bad I do not have the budget to just buy two Intel (or > other) SSDs of similar size and see if the timeouts disappear.. > > I wonder if this is a firmware issue with the drive or just some > misguided fancy energy saving feature of this particular drive > model causing the whole trouble.I don't think it's the SSDs, as I'm seeing the exact same behaviour using 4 2TB WD Reds in a raidz1 with 10.1-RELEASE on a HP N40L as well. Whenever I do heavy reads like a scrub or send, there are CAM timeouts and eventually the drives detach. I had to downgrade to 10.0-RELEASE, which seems to work fine so far. The box ran Ubuntu until recently, without issues. I am happy to troubleshoot further, should anyone want to pick this up. I'm relatively new to FreeBSD, so any guidance on next steps to take is welcome. p
Steven Hartland
2014-Dec-22 14:26 UTC
10.1 RC4 r273903 - zpool scrub on ssd mirror - ahci command timeout
On 22/12/2014 14:09, Peter HEINER wrote:>> So I now think the whole problem centers around the Samsung 850 PRO >> 512GB SSDs. Too bad I do not have the budget to just buy two Intel (or >> other) SSDs of similar size and see if the timeouts disappear.. >> >> I wonder if this is a firmware issue with the drive or just some >> misguided fancy energy saving feature of this particular drive >> model causing the whole trouble. > I don't think it's the SSDs, as I'm seeing the exact same behaviour > using 4 2TB WD Reds in a raidz1 with 10.1-RELEASE on a HP N40L as well. > Whenever I do heavy reads like a scrub or send, there are CAM timeouts > and eventually the drives detach. I had to downgrade to 10.0-RELEASE, > which seems to work fine so far. The box ran Ubuntu until recently, > without issues. > I am happy to troubleshoot further, should anyone want to pick this up. > I'm relatively new to FreeBSD, so any guidance on next steps to take is > welcome.Are all the disks your seeing errors with running at 6Gbps? If so have you tried downgrading the connection to SATA 2 speeds to see if that makes a difference? An example of this which goes in /boot/loader.conf is: hint.ahcich.0.sata_rev="2" We had a similar problem with a Dell chassis where the connection via the Hotswap backplane wasn't up to scratch for SATA 3 speeds, and this fixed it. Regards Steve