[rrd-developers] Accelerator Daemon

[Florian Forster]

Hi Bernard,

On Mon, Jun 30, 2008 at 02:00:57PM -0700, Bernard Li wrote:
> > Yes, that's probably right. I didn't expect anyone with such a huge
> > number of RRD files to generate graphs periodically/statically
> > instead of on demand/dynamically.. Is anyone with a big number of
> > files doing that? If so: Why?
> 
> I am not sure if Ganglia fits your description, but I will describe
> what it does.

as far as I know (and see) Ganglia fit's my view of how big setups work
exactly: There are RRD files which are updated often and graphs (i. e.
PNG or GIF images) which are generated by a CGI script or PHP module
``on demand'' (i. e. rarely). So Gnaglia setups will benefit from
``rrdcached'' a lot, I think..

The setups that will not benefit from that daemon generate the _graphs_
often, i. e. every time they update the RRD files. They would do
something like this, for example:
  VALUE=`cat | grep | sort | whatnot`
  rrdtool update $FILE N:$VALUE
  rrdtool graph /www/$FILE.hour.png -s -3600 ...
  rrdtool graph /www/$FILE.day.png  -s -86400 ...
  ...

Regards,
-octo
-- 
Florian octo Forster
Hacker in training
GnuPG: 0x91523C3D
http://verplant.org/
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 189 bytes
Desc: Digital signature
Url : http://lists.oetiker.ch/pipermail/rrd-developers/attachments/20080630/f8f0eabb/attachment.bin