Re: [9fans] Changelogs & Patches?

[Roman Shaposhnik <rvs@sun.com>]

On Jan 26, 2009, at 9:37 AM, erik quanstrom wrote:
> the other part of the argument — the "write hole"
> depends on two things that i don't think are universal
> a) zfs' demand for transactional storage

Huh?!?

> b) a particular raid implentation.
>
> fancy raid cards

I think you missed what I in RAID is supposed to
be expanding into ;-)

>  i don't have any nda that let me see the firmware for a variety of  
> raid
> devices, but i find it hard to believe that all raid vendors
> rewrite the entire stripe whever the write is smaller than
> the stripe size and all could rewrite the data before the
> parity.

Fancy ones might try to do fancy things, but see above.

> why do you think that mpi has anything to do with
> a plan 9 infastructure?

It is the other way around: the fact that Plan9 still
doesn't have anything to do with MPI keeps it
away from the kind of clusters Ron used to care
about (although, in reality, it is all about gcc anyway,
so MPI is a lesser argument here).

>> May be your numbers are wrong, may be your usage
>> patterns are different. Who knows.
>
> a single cpu on ec2 costs $150/month.

I don't know where did you get that #, but my instance
on EC2 costs me about $70/m. Oh, wait! I know!
It is all because Solaris is so energy efficient ;-)

> the machines i have largely cost less than $500.  so
> that's like $14/month.  that doesn't change the equation
> much.

I believe you are distorting my argument on purpose.

So lets just drop this conversation, ok?

Thanks,
Roman.