Hi, Thank you every much! I found MSI in my system too and there are some errors found in bios log. Replace the memorys can fix it.
L2GW_2680:/home/fsp/ycb # perf stat -C 1-11,14-25,29-39,42-52 --smi-cost ^C Performance counter stats for 'CPU(s) 1-11,14-25,29-39,42-52': SMI cycles% SMI# -0.2% 90 4472.483413712 seconds time elapsed -----Original Message----- From: Arnaldo Carvalho de Melo [mailto:arnaldo.m...@gmail.com] Sent: 2019年4月16日 1:59 To: Paul Clarke <p...@us.ibm.com> Cc: Linhaifeng <haifeng....@huawei.com>; linux-perf-us...@vger.kernel.org; linux-kernel@vger.kernel.org Subject: Re: perf tools:Is there any tools to found out the max latency by irq or cpu idle Em Mon, Apr 15, 2019 at 07:52:59AM -0500, Paul Clarke escreveu: > On 4/13/19 1:01 AM, Linhaifeng wrote: > > Sorry, the value 131081408 is just for example. Actually the result is like > > this: > > sqrt 2019-04-10 23:53:50: 43968 > > sqrt 2019-04-10 23:53:51: 44060 > > sqrt 2019-04-10 23:53:52: 49012 > > sqrt 2019-04-10 23:53:53: 38172 > > sqrt 2019-04-10 23:53:54: 131081408 sqrt 2019-04-10 23:53:55: > > 43600 sqrt 2019-04-10 23:53:56: 46704 sqrt 2019-04-10 23:53:57: > > 46880 sqrt 2019-04-10 23:53:58: 44332 …… sqrt 2019-04-10 > > 02:17:15: 136345876 …… sqrt 2019-04-10 04:40:35: 136335644 …… > > Given the periodicity, I'm wondering if it could be System Management > Interrupts (SMIs)? > > If so, some BIOSes have settings to mitigate, otherwise, there's not much > that can be done, per my understanding. [root@quaco perf]# perf list smi List of pre-defined events (to be used in -e): msr/smi/ [Kernel PMU event] sunrpc:xprt_transmit [Tracepoint event] tcp:tcp_retransmit_skb [Tracepoint event] tcp:tcp_retransmit_synack [Tracepoint event] sdt_qemu:qmp_block_job_dismiss [SDT event] sdt_qemu:qmp_job_dismiss [SDT event] Metric Groups: [root@quaco perf]# Here, using it: [root@quaco perf]# perf stat -I 1000 -e msr/smi/ # time counts unit events 1.000919819 0 msr/smi/ 2.001689950 0 msr/smi/ 3.002266988 0 msr/smi/ 4.003049439 16 msr/smi/ 5.003676064 0 msr/smi/ 6.004420613 16 msr/smi/ ^C 6.609405666 0 msr/smi/ [root@quaco perf]# In this Lenovo T480s I generate SMIs by pressing the mute button :-) - Arnaldo
