[rrd-users] Re: Real Time monitoring

[Tobias Oetiker]

Today Pradeep Hodigere wrote:

>
> Hi,
>
>   Can RRD be used by tools that need to read data off
> the RRD files at 2 second intervals? The number of
> DS's are about 40 and there are 5 RRA's. Writing into
> the RRD files seems to be happening realtime but
> reading off of it by the display tools seems to take
> longer than 7 seconds. I'm not sure on the cause of
> the reading delay.
>
>  Please let me know if RRD can be used when it comes
> to real-time monitoring.

Hi pradeep,

reading is much more costly than writing, because of the internal
structure of rrd files, writing to them is as fast as it gets, I
doubt that you can devise a file structure which will do it much
more efficiently than rrd. But for reading, all the data has to be
read, and a graph has to be generated. This takes time ... if you
wanted todo a realtime scrolling graph it would make sense to only
read bits of the data a time and graph them and push the graph
along as you go ... rrdtool graph can not do this, but you could
certainly implement it

tobi
>
> Thanks,
> pradeep
>
> __________________________________________________
> Do You Yahoo!?
> Yahoo! Health - your guide to health and wellness
> http://health.yahoo.com
>
> --
> Unsubscribe mailto:rrd-users-request at list.ee.ethz.ch?subject=unsubscribe
> Help        mailto:rrd-users-request at list.ee.ethz.ch?subject=help
> Archive     http://www.ee.ethz.ch/~slist/rrd-users
> WebAdmin    http://www.ee.ethz.ch/~slist/lsg2.cgi
>
>

-- 
 ______    __   _
/_  __/_  / /  (_) Oetiker, ETZ J97, ETH, 8092 Zurich, Switzerland
 / // _ \/ _ \/ / phoneto:+41(0)1-632-5286  faxto:+41(0)1-632-1517
/_/ \.__/_.__/_/ oetiker at ee.ethz.ch http://google.com/search?q=tobi


--
Unsubscribe mailto:rrd-users-request at list.ee.ethz.ch?subject=unsubscribe
Help        mailto:rrd-users-request at list.ee.ethz.ch?subject=help
Archive     http://www.ee.ethz.ch/~slist/rrd-users
WebAdmin    http://www.ee.ethz.ch/~slist/lsg2.cgi