The Linux Kernel Mailing List
 help / color / mirror / Atom feed
From: ALOK TIWARI <alok.a.tiwari@oracle.com>
To: christian.loehle@arm.com, rafael.j.wysocki@intel.com,
	daniel.lezcano@linaro.org, linux-pm@vger.kernel.org
Cc: gregkh@linuxfoundation.org, sashal@kernel.org,
	linux-kernel@vger.kernel.org,
	"stable@vger.kernel.org" <stable@vger.kernel.org>
Subject: [report] Performance regressions introduced via "cpuidle: menu: Remove iowait influence" on 6.12.y
Date: Wed, 3 Dec 2025 23:01:13 +0530	[thread overview]
Message-ID: <c0b5c308-ea18-4736-b507-01cb06cb8dfc@oracle.com> (raw)

Hi,

I’m reporting a performance regression of up to 6% sequential I/O
vdbench regression observed on 6.12.y kernel.
While running performance benchmarks on v6.12.60 kernel the sequential 
I/O vdbench metrics are showing a 5-6% performance regression when 
compared to v6.12.48

Bisect root cause commit
========================
- commit b39b62075ab4 ("cpuidle: menu: Remove iowait influence")

Things work fine again when the previously removed 
performance-multiplier code is added back.

Test details
============
The system is connected to a number of disks in disk array using 
multipathing and directio configuration in the vdbench profile.

wd=wd1,sd=sd*,rdpct=0,seekpct=sequential,xfersize=128k
rd=128k64T,wd=wd1,iorate=max,elapsed=600,interval=1,warmup=300,threads=64


Thanks,
Alok

             reply	other threads:[~2025-12-03 17:31 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-12-03 17:31 ALOK TIWARI [this message]
2025-12-24 12:18 ` [report] Performance regressions introduced via "cpuidle: menu: Remove iowait influence" on 6.12.y ALOK TIWARI
2025-12-24 13:26   ` Christian Loehle
2025-12-29 16:17     ` Doug Smythies

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=c0b5c308-ea18-4736-b507-01cb06cb8dfc@oracle.com \
    --to=alok.a.tiwari@oracle.com \
    --cc=christian.loehle@arm.com \
    --cc=daniel.lezcano@linaro.org \
    --cc=gregkh@linuxfoundation.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pm@vger.kernel.org \
    --cc=rafael.j.wysocki@intel.com \
    --cc=sashal@kernel.org \
    --cc=stable@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox