unknown
1970-01-01 00:00:00 UTC
I'd imagine you'd want the stripesize of this striped LV to match the
underlying RAID6 stripesize no? So 2560K, e.g. -i 3 -I 2560
That makes for a very large full stripe through...
minimum_io_size and optimal_io_size) by the striped LV.
But if not you definitely don't want to be trying to pierce through the
striped LV config to establish settings of the underlying RAID6. Each
layer in the stack should respect the layer beneath it. So, if the
striped LV is configured how you'd like, you should only concern
yourself with the limits that have been established for the topmost
striped LV that you're layering XFS on.
underlying RAID6 stripesize no? So 2560K, e.g. -i 3 -I 2560
That makes for a very large full stripe through...
Hence, stripe of the 3 RAID6 in a LV.
And here is my first question: How can I check if the storage and the LV
are correctly aligned?
mkfs.xfs -d su=256k,sw=10 -l size=128m,lazy-count=1 /dev/dcvg_a/dcpool
So my second question is, are the above 'su' and 'sw' parameters correct on
the current LV configuration? If not, which values should I have and why?
AFAIK su is the stripe size configured in the controller side, but in this
case we have a LV. Also, sw is the number of data disks in a RAID, but
again, we have a LV with 3 stripes, and I am not sure if the number of data
disks should be 30 instead.
Newer versions of mkfs.xfs _should_ pick up the hints exposed (asAnd here is my first question: How can I check if the storage and the LV
are correctly aligned?
mkfs.xfs -d su=256k,sw=10 -l size=128m,lazy-count=1 /dev/dcvg_a/dcpool
So my second question is, are the above 'su' and 'sw' parameters correct on
the current LV configuration? If not, which values should I have and why?
AFAIK su is the stripe size configured in the controller side, but in this
case we have a LV. Also, sw is the number of data disks in a RAID, but
again, we have a LV with 3 stripes, and I am not sure if the number of data
disks should be 30 instead.
minimum_io_size and optimal_io_size) by the striped LV.
But if not you definitely don't want to be trying to pierce through the
striped LV config to establish settings of the underlying RAID6. Each
layer in the stack should respect the layer beneath it. So, if the
striped LV is configured how you'd like, you should only concern
yourself with the limits that have been established for the topmost
striped LV that you're layering XFS on.