[OpenIndiana-discuss] Hitachi 4 TB disks + HP Microserver + OI 151 + ZFS

[Roy Sigurd Karlsbakk]

> > For some time now I've successfully been using ZFS RAIDz pools made
> > up of 3 x 1
> > TB or 3 x 2 TB Western Digital Caviar Black disks in a HP
> > MicroServer N36L
> > running OI 148 or 151. I'm now thinking of using the newer HP N40L
> > microserver
> > with 3 x 4 TB disks (Hitachi DeskStart 7K4000) which have 4096 byte
> > sectors. Can
> > anyone foresee a problem with this?
>
> i have been using oi-151a1 on hp n40L for 6 months without problems.
> my pool is
> smaller than yours and i do not have 4k disks.
> 
> if you look at the quick specs of the n40l:
> 
> Maximum internal SATA storage capacity of up to 8.0TB (4 x 2TB 3.5"
> SATA drives)
> 
> 2TB 3G SATA 7.2K, Up to 4, SATA controller with Embedded RAID on
> Motherboard
> 
> maybe 2 4tb disk would work, but for sure not 3 of them

If one works, 10 or 100 will. The only known issue with 4k sector drives, is alignment issues. Since the drives lie about the sector size, reporting 512B logical sectors, while really having 4kiB sectors, the OS cannot foresee real alignment, and may align partitions/filesystems to the reported 512B size, so in case of overlap, multiple I/O operations may be issued to the same physical sector. Patches for zpool has been submitted to fix this, but was, for various reasons, rejected. I don't know the current status for these.

Vennlige hilsener / Best regards

roy
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Roy Sigurd Karlsbakk
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roy at karlsbakk.net
http://blogg.karlsbakk.net/
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