Re: skip raid5 reconstruction

[Brad Campbell <brad@wasp.net.au>]

Ming Zhang wrote:
> Hi folks
> 
> I am testing some HW performance with raid5 with 2.4.x kenrel.
> 
> It is really troublesome every time I create a raid5, wait 4 hours for
> reconstruction, and then test some data and then recreate another one
> and wait again. I wonder if there is any hack or option available to
> create a raid5 without reconstruct the parity disk. I just have interest
> to test the performance so do not care about data correctness at this
> stage.

I did a similar thing a while back.
I created the raid and waited for it to sync, I then make dd copies of the raid superblocks.
When I blew it up I just dd the clean superblocks back again (saved a 12 hour rebuild time)

Having just thought about what you wrote, I guess you are building the raid in different
configurationes each time, so my method might not be good for you.

Regards,
Brad
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