Re: periodic iowait spike

From: Toralf FÃrster
Date: Wed May 13 2015 - 08:50:04 EST


On 05/03/2015 12:02 PM, Toralf FÃrster wrote:
> The picture in [1], created with isag from the sysstat package, shows a periodic spike in the iowait of my tinderbox server (hardened Gentoo 3.19.6-r1), correlating to write transactions per seconds from a similar graph.
>
> I'm wondering what (kernel, btrfs or ?) is causing this.
>
>
> [1] http://www.zwiebeltoralf.de/pub/sar_cpu_3rdMay.png
>
After I deleted from that 3 TB drive (1.2 TB were filled, 1.6 TB were free) about 0.5 TB, the spikes went away.
I'm wondering that such spikes happen although the drive had more than 50 % free space ...


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Toralf
pgp key: 7B1A 07F4 EC82 0F90 D4C2 8936 872A E508 0076 E94E
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"; the past is all dirty and cruel in the modern popular imagination, with the exception of the Romans, who are just cruel"
Ian Mortimer, 2008, "The Time Traveller's Guide to Medieval England"
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