[CentOS] Analyzing the MBR

Thu Jun 5 22:10:03 UTC 2014
Les Mikesell <lesmikesell at gmail.com>

On Thu, Jun 5, 2014 at 5:06 PM, John R Pierce <pierce at hogranch.com> wrote:
> On 6/5/2014 2:50 PM, Les Mikesell wrote:
>> New bigger disks may use 4k physical sectors but report 512 for
>> backwards compatibility.  If you don't write 4 contiguous sectors it
>> has to read, wait for the disk to spin back around, then write,
>> merging in what you did write.  Which means writes will be very slow
>> if your partitions are not aligned on 4k boundaries. I haven't had to
>> deal with many of these yet so I've mostly just installed gparted from
>> epel and used its defaults rather than doing the math myself.
> some new disks even report they are 4K and allow 4K sector operations,
> which file systems like XFS support natively.   This is going to be
> increasingly common going forwards.
> [btw, thats 8 consecutive 512B sectors for 4K]

Ummm, yeah.... That's why I let gparted do the math.

   Les Mikesell
     lesmikesell at gmail.com