[Serusers] Replication problem
andreas.granig at inode.info
Mon Aug 1 14:24:30 CEST 2005
Greger V. Teigre wrote:
> :-) Jan participated in a discussion on serusers on a new cache system
> where all locations where not loaded at start-up, but rather at need.
Well, I just read the thread at
http://lists.iptel.org/pipermail/serusers/2005-May/019867.html and for me
as a guy who wants to run a scalabe system with a minimum of afford and
as soon as possible, one question comes up: is it really worth the
efford to implement such a caching system?
Don't understand me wrong, I'm sure there are a lot of people who
benefit from this caching mechanism in terms of performance, but my
experience with this is, well, very bad, when using it in a bigger
For me (and I think a lot of other people, like Paul, who mentioned it
too in the above thread) the performance won due to the cache lookup is
so minimal in combination with my 10-15 other mysql queries and 1-2 enum
queries per call, that I really don't care, especially when thinking
about the advantages of a consistend location table in the backend DB:
No need to replicate on SIP level anymore (and there's no really usable
mechanism for that for more than two SER nodes), no need to distribute
other contacts like aliases to every single SER node using a remote fifo
hack, the need of much less memory, much faster startup time and so on,
and that all for just a few more milliseconds of latency.
So IMHO the option of disabling the cache absolutely makes sense *in
some circumstances*, like large scale systems.
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