[rrd-developers] implementing portable format - change format?

[Tobias Oetiker]

Hi Igor,

the constant size is good news ...

for a realistic simulation you have to have 10-20k rrd file
aequivalents ... since the caching effect is a rather important
part of the equation.

cheers
tobi

Today Sfiligoi Igor wrote:

> kevin brintnall wrote:
> > On Mon, Nov 17, 2008 at 12:14:04PM -0600, Sfiligoi Igor wrote:
> >> Running a simple open/update/close loop, I get ~9 updates per second:
> >
> > Igor, what kind of rates can you get with RRD update on the same hardware?
> >
>
> I get ~350 updates per second using plain rrdtool update invocations:
> bash-3.2$ rrdtool create t1.rrd DS:val:GAUGE:300:0:200000 RRA:LAST:0.9:1:100
> bash-3.2$ date; for ((i=0; $i<10000; i++)); do rrdtool update t1.rrd
> N:$RANDOM; done; date
> Mon Nov 17 12:40:20 CST 2008
> Mon Nov 17 12:40:48 CST 2008
> bash-3.2$ date; for ((i=0; $i<10000; i++)); do rrdtool update t1.rrd
> N:$RANDOM; done; date
> Mon Nov 17 12:41:00 CST 2008
> Mon Nov 17 12:41:28 CST 2008
>
> bash-3.2$ rrdtool create t2.rrd DS:val:GAUGE:300:0:200000
> RRA:LAST:0.9:1:2000
> bash-3.2$ date; for ((i=0; $i<10000; i++)); do rrdtool update t2.rrd
> N:$RANDOM; done; date
> Mon Nov 17 12:41:35 CST 2008
> Mon Nov 17 12:42:03 CST 2008
> bash-3.2$ date; for ((i=0; $i<10000; i++)); do rrdtool update t2.rrd
> N:$RANDOM; done; date
> Mon Nov 17 12:42:08 CST 2008
> Mon Nov 17 12:42:37 CST 2008
>
>
> Indeed, sqlite approach seems to be viable only when grouping together
> many updates into a singular transaction:
>    1 row update/transaction  =    ~9Hz
>   10 row updates/transaction =   ~85Hz
>  100 row updates/transaction =  ~800Hz
>
> Igor
>
>

-- 
Tobi Oetiker, OETIKER+PARTNER AG, Aarweg 15 CH-4600 Olten, Switzerland
http://it.oetiker.ch tobi at oetiker.ch ++41 62 775 9902 / sb: -9900