[ClusterLabs] Antw: Antw: notice: throttle_handle_load: High CPU load detected

[Andrew Beekhof]

> On 27 May 2015, at 10:09 pm, Kostiantyn Ponomarenko <konstantin.ponomarenko at gmail.com> wrote:
> 
> I think I wasn't precise in my questions.
> So I will try to ask more precise questions.
> 1. why the default value for "load-threshold" is 80%?

Experimentation showed it better to begin throttling before the node became saturated.

> 2. what would be the impact to the cluster in case of "load-threshold=100%”?

Your nodes will be busier.  Will they be able to handle your load or will it result in additional recovery actions (creating more load and more failures)?  Only you will know when you try.

> 
> Thank you,
> Kostya
> 
> On Mon, May 25, 2015 at 4:11 PM, Kostiantyn Ponomarenko <konstantin.ponomarenko at gmail.com> wrote:
> Guys, please, if anyone can help me to understand this parameter better, I would be appreciated.
> 
> 
> Thank you,
> Kostya
> 
> On Fri, May 22, 2015 at 4:15 PM, Kostiantyn Ponomarenko <konstantin.ponomarenko at gmail.com> wrote:
> Another question - is it crmd specific to measure CPU usage by "I/O wait"?
> And if I need to get the most performance of the running resources in cluster, should I set "load-threshold=95%" (or even 100%)?
> Will it impact the cluster behavior in any ways?
> The man page for crmd says that it will "The cluster will slow down its recovery process when the amount of system resources used (currently CPU) approaches this limit".
> Does it mean there will be delays in cluster in moving resources in case a node goes down, or something else?
> I just want to understand in better.
> 
> That you in advance for the help =)
> 
> P.S.: The main resource does a lot of disk I/Os.
> 
> 
> Thank you,
> Kostya
> 
> On Fri, May 22, 2015 at 3:30 PM, Kostiantyn Ponomarenko <konstantin.ponomarenko at gmail.com> wrote:
> I didn't know that.
> You mentioned "as opposed to other Linuxes", but I am using Debian Linux.
> Does it also measure CPU usage by I/O waits?
> You are right about "I/O waits" (a screenshot of "top" is attached).
> But why it shows 50% of CPU usage for a single process (that is the main one) while "I/O waits" shows a bigger number?
> 
> 
> Thank you,
> Kostya
> 
> On Fri, May 22, 2015 at 9:40 AM, Ulrich Windl <Ulrich.Windl at rz.uni-regensburg.de> wrote:
> >>> "Ulrich Windl" <Ulrich.Windl at rz.uni-regensburg.de> schrieb am 22.05.2015 um
> 08:36 in Nachricht <555EEA72020000A10001A71D at gwsmtp1.uni-regensburg.de>:
> > Hi!
> >
> > I Linux I/O waits are considered for load (as opposed to other Linuxes) Thus
> ^^ "In"                                                                                              s/Linux/UNIX/
> 
> (I should have my coffee now to awake ;-) Sorry.
> 
> 
> 
> 
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