From mboxrd@z Thu Jan  1 00:00:00 1970
Date: Mon, 26 Jan 2009 20:45:50 -0800
From: Roman Shaposhnik <rvs@sun.com>
In-reply-to: <99929e006b16e4cacada830f7c01cd37@quanstro.net>
To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net>
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References: <99929e006b16e4cacada830f7c01cd37@quanstro.net>
Subject: Re: [9fans] Changelogs & Patches?
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On Jan 26, 2009, at 8:39 AM, erik quanstrom wrote:
>> This approach will work too. But it seems that asking fossil
>> to verify a checksum when the block is about to go to venti
>> is not that much of an overhead.
>
> if checksumming is a good idea, shouldn't it be available outside
> fossil?

It is available -- in venti ;-)

> perhaps the argument is that it might be more efficient
> to implement this inside fossil.

The argument has nothing to do with the efficiency. However
the way fossil is structured -- I think you're right it won't be
able to get additional benefits from its own checksuming.

>  while this might be the case, i
> don't see how the small overhead of a sd layer would matter
> when you're assuming an ec2-style service, which will have a
> minimum latency in the 10s of milliseconds.

Somehow you've got this strange idea that I'm engineering
something for ec2-style services. I am not. EC2 was a simple
example I used once. If it agitates you too much I promise
not too use it in the future ;-)

Thanks,
Roman.