rrdtool performance tuning (fwd)

[Oleg Derevenetz]

> [hmm, after thinking a bit I decided it would be more appropriate here, in
> stable@]
>
> Dear colleagues,
>
> any hints to tune rrdtool with ~30k rrd files (approx 2k target devices)?
>
> machine is mostly IO-bound, showing 100% disk load with 8 or sometimes 
> even 3
> mB/s, 300-400 tps (it's 2 SATA300 disks in gmirror)

For example, update algorythm can be changed. Try to not update RRD files 
simultaneously, queue update data instead (with timestamps), for example, in 
memory, and periodically do a "bulk update" using a single rrdupdate call 
for all queue items related to single RRD file. This saves I/O a lot, for 
example, in my NMS (TclMon) I use simular scheme, and now it updates >50K 
RRD files with 5-10 variables each. I/O load is 100-150 tps with 1-1.5MB/s 
throughput.

--
Oleg Derevenetz <oleg at vsi.ru> OOD3-RIPE
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