On 14/10/10 02:27, Eugene Vilensky wrote: > One more question...is there anything to be concerned about regarding > on disk geometry or does the PERC do the right thing automatically > when using OEM drives? >
Nearly all drives have 512byte sectors, so these won't be a problem. WD have been shipping 1.5TB and 2TB drives with 4k sectors for a while, and Hitachi is now also (just) doing so. In the case of the WD drives, they lie that they have a 512byte physical sectors, because if they don't various BIOS and software breaks (dunno about the Hitachis). So, if you're using those drives, then the PERC had better align it's user-visible data on 4096 byte boundries, otherwise write performance will go down the toilet (unaligned write of 4k of data will result in 2 reads and 2 writes instead of a single write). Dunno if it does or not, I guess you could pull a drive an use dmraid to work out what it's doing (the RAID metadata it uses is an open standard). Tim. -- South East Open Source Solutions Limited Registered in England and Wales with company number 06134732. Registered Office: 2 Powell Gardens, Redhill, Surrey, RH1 1TQ VAT number: 900 6633 53 http://seoss.co.uk/ +44-(0)1273-808309 _______________________________________________ Linux-PowerEdge mailing list [email protected] https://lists.us.dell.com/mailman/listinfo/linux-poweredge Please read the FAQ at http://lists.us.dell.com/faq
