Re: High CPU usage after upgrading from Debian 7 to Debian 9

On 16.04.19 17:22, Алексей wrote:
>Thanks for your answer.
>
>I have Intel(R) Xeon(R) CPU E3-1220 v3 @ 3.10GHz inside - no HT on it.
>
>And I already have CPU microcode installed:
>
>dpkg -l | grep microcode
>ii  amd64-microcode                   3.20160316.3                   amd64        Processor microcode firmware for AMD CPUs
>ii  intel-microcode                   3.20180807a.1~deb9u1           amd64        Processor microcode firmware for Intel CPUs

>Do you think removing it would help?

you surely don't need amd64-microcode, you can try uninstalling
intel-microcode to see if it helps.

I think there are some option to disable spectre/meltdown mitigation in the
kernel, just haven't found them yet... you can try to search for them

>Also I have Broadcom network adapters - if it is important:

should not be.

>15 апреля 2019, 11:45:37, от "Matus UHLAR - fantomas" <[email protected]>:
>
>On 15.04.19 11:05, Алексей wrote:
>>I have two Debian boxes acting as a routesr (+iptables +quagga(BGP)). I have updated one from Debian 7 to Debian 9 recently and now experience 2x CPU utilization on the same amounts of traffic, e.g. on normal load of 1Gbps (real-world traffic) Debian 7 had 5-6% and Debian 9 has 10-12% softirq CPU time. This behaviour can also be observed during tests - 6Gbps iperf gets 3% on Debian 7 and 6% on Debian 9.
>>
>>I compared ethtool -k outputs on both boxes and they are pretty similar. Syslog doesn't show anything suspicious.
>>
>>Did anyone have the similar issue? Or can give me some advice on troubleshooting?
>
>we have noticed something similar due to the spectre/meltdown updates.
>Turning off HT cpus did help much.
>not installing the CPU microcode should help too.