From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <68a46edfa8e40c2fc74da101e3dbe24b@terzarima.net>
To: weigelt@metux.de, 9fans@cse.psu.edu
Subject: Re: [9fans] thoughs about venti+fossil
From: Charles Forsyth <forsyth@terzarima.net>
Date: Thu,  6 Mar 2008 15:09:40 +0000
In-Reply-To: <20080306064002.GD18329@nibiru.local>
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> But for HA applications, we still need some additional redundancy
> or at least some error diagnostics at application level. Well,
> we'll most likely needs this anyways, eg. to detect human fault
> or code bugs.

i hadn't realised the code i'd quoted only dealt with blocks in memory
(i didn't look hard enough once i'd found it), but russ then pointed out
that another option will do something like the check i'd intended.

given that, you have at least a check and a diagnostic that the
unlikely event ocurred.  it isn't the case i'd worry about first.  after all, the applications
pull the stuff into memory across interfaces that might have at most a parity
check, after transmission using protocols that use a fairly simple 16-bit
check sum, a compromise between speed of calculation and effectiveness.
one might sometimes add an end-to-end check, or digesting ... perhaps using SHA1!