Funding Cyrus High Availability

[Michael Loftis]

--On Monday, September 20, 2004 00:43 +0200 Jure Pe ar 
<pegasus at nerv.eu.org> wrote:

> On Sun, 19 Sep 2004 00:52:08 -0700 (PDT)
> David Lang <david.lang at digitalinsight.com> wrote:
>
> Nice review of replication ABC :)
>
> Here are my thoughts:
>
>> 1. Active->Slave replication with manual failover
>
> This is really the simplest way to do it. Rsync (and friends) does 90% of
> the required job here; the only thing it's lacking is the concept of the
> "mailbox" as a unit. It would be nice if our daemon here would do its job
> in an atomic way.
> A few days ago someone was asking for an event notification system that
> would be able to call some program when a certain action happened on a
> mailbox. Something like this would come handy here i think :)

we were doing this but really, rsync does not scale well.  when you get 
lots of small files it takes it loner to figure out what to transfer, than 
it'd take to just transfer almost everything over (assuming a small 768kbit 
to about 1.5mbit link and a average sized messages mailstore).  and unles 
you break it up into smaller chunks, it'll gobble up wads of RAM during the 
process.  insane amounts like well over a gig or so for our mailstore with 
about humm 51Gb of mail.  Not exactly sure the number of files off the top 
of my head though it could be figured if wanted.

---
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