rrdtool performance tuning (fwd)

[Dmitry Morozovsky]

On Mon, 29 Oct 2007, Alfred Perlstein wrote:

AP> * Dmitry Morozovsky <marck at rinet.ru> [071029 12:44] wrote:
AP> > 
AP> > [hmm, after thinking a bit I decided it would be more appropriate here, in 
AP> > stable@]
AP> > 
AP> > Dear colleagues,
AP> > 
AP> > any hints to tune rrdtool with ~30k rrd files (approx 2k target devices)?
AP> > 
AP> > machine is mostly IO-bound, showing 100% disk load with 8 or sometimes even 3 
AP> > mB/s, 300-400 tps (it's 2 SATA300 disks in gmirror)
AP> 
AP> More ram?

Already 2G, mostly inactive/free.

AP> 
AP> Turn off atime?

For sure, and even tried to move rrd data to smaller UFS2 - same result.

AP> Hash the data files into multiple directories to avoid having 2k files
AP> in one dir.

Hmm, I thought 2k is not so much, especially where UFSDIRHASH is in place...

AP> Not sure how rrd tool works internally, but it might make sense
AP> to see if you can use some layering library to force it to cache
AP> some open files per process or something.

It seems it using a lot of mmap...




Sincerely,
D.Marck                                     [DM5020, MCK-RIPE, DM3-RIPN]
[ FreeBSD committer:                                 marck at FreeBSD.org ]
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*** Dmitry Morozovsky --- D.Marck --- Wild Woozle --- marck at rinet.ru ***
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