A5000: no NVRAM?

[V.Sander]

>But NVRAM once made a conceptual sense in the SSA 100 series. Why not
>in the A5000? (power failures etc). I understand that the optical
>medium is going from host to disk directly. But how are asynchronous
>I/O (fastwrites it was called in the SSA 100) etc handled in the A5000?


Surely there are some disadvantages in the absence of NVRAM. But you
have no controller as the original SSA series had. All is handled by
the attached system.

The main idea of the design was, that one should stripe I/O to handle 
performance similar - or even faster than 25 MB FC -  
than writing to the NVRAM. Each disk is be able to deliver performance
of 10 MB/s. One should be able to fill the FC-AL by striping disks, why
using NVRAM?

Volker

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    Volker Sander	
    Zentralinstitut fuer Angwandte Mathematik  
    Forschungszentrum Juelich GmbH
    52425 Juelich	

    E-mail: V.Sander@fz-juelich.de
    Phone:  (+49) 2461 / 61- 6586   
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