[Users] monitor VE ressources usage

[jehan procaccia]

Chris Bennett a écrit :
> Hi Jehan,
>
>   
>> but no way, a simple "yum list" takes up to 2mn, while on the slower
>> hard node running vservers containers it took only 30s ! (same
>> repository and "yum clean all" before )
>>     
>
> This sounds like different defaults - OpenVZ containers default to
> 256M of memory on my Centos5 system, while vserver containers have no
> limits imposed by default.
>
> Yum's performance may be choked by the availablility of memory.
>
> Regards,
>
> Chris Bennett
> cgb
>   
yes you are right, but I used to limit memory on my vservers
 rlimits # cat rss
524288
however I forgot it was 4K page unit, so here my vserver was'nt 512M but 
2Gbyte memory !

So I set the same on my openVZ VE
# vzctl set 21230 --privvmpages $((256 * 2048)) --save
# vzctl set 21230 --vmguarpages $((256 * 256)) --save

=> I fugured out that this would set 2G of ram max with a guarentee of 
256M, am I correct ?is that the right way to add memory to my VE ?

but no change at all, indeed "yum list" is not the best benchmark, but 
that's one of the daily sysdmins tool ;-) , moreover during install 
periods ... anyway, after adding that memory it still take the same 
amount of time (2mn) :-( .

then I tought it could come from cpu shortage, so I largely increased 
it, from --cpuunits 6000 --cpulimit 10 to :
#  vzctl set 21230 --cpuunits 200000 --cpulimit 40 --save
# vzcpucheck -v
VEID            CPUUNITS
-------------------------
0               1000
200             1000
201             1000
202             1000
203             1000
21233           6024
21230           250000
Current CPU utilization: 261024
Power of the node: 1263400

Now thing are far better , it takes 20s to run yum list :-) , even after 
seting things back to 1G of privvmpages and --cpuunits 100000 --cpulimit 
20 the VE takes a reasonable 40s to run yum list , i'll stick with it .

Just to be sure , how much of the "Power of the node: 1263400" can I 
take for VEs ? How much should I leave for the Hard Node ?

Thanks.