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Subject: Re: ZFS stalled after some mirror disks were lost
To: Ben RUBSON <ben.rubson@gmail.com>, Steven Hartland <smh@FreeBSD.org>
References: <4A0E9EB8-57EA-4E76-9D7E-3E344B2037D2@gmail.com>
Cc: Freebsd fs <freebsd-fs@FreeBSD.org>
From: Andriy Gapon <avg@FreeBSD.org>
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Date: Tue, 3 Oct 2017 09:12:49 +0300
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On 02/10/2017 21:12, Ben RUBSON wrote:
> A sustained read throughput of 180 MB/s, 45 MB/s on each iscsi disk
> according to "zpool iostat", nothing on local disks (strange but I
> noticed that IOs always prefer iscsi disks to local disks).

Are your local disks SSD or HDD?
Could it be that iSCSI disks appear to be faster than the local disks to the
smart ZFS mirror code?

Steve, what do you think?

-- 
Andriy Gapon