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[31.46.246.60]) by smtp.gmail.com with ESMTPSA id p2-20020a1709060e8200b00a46cddf1efbsm2927821ejf.29.2024.03.25.03.36.38 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 25 Mar 2024 03:36:38 -0700 (PDT) Sender: Ingo Molnar Date: Mon, 25 Mar 2024 11:36:36 +0100 From: Ingo Molnar To: Shrikanth Hegde Cc: peterz@infradead.org, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, qyousef@layalina.io, linux-kernel@vger.kernel.org, vschneid@redhat.com Subject: Re: [PATCH v3 0/2] sched: Minor changes for rd->overload access Message-ID: References: <20240325054505.201995-1-sshegde@linux.ibm.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240325054505.201995-1-sshegde@linux.ibm.com> * Shrikanth Hegde wrote: > v2 -> v3: > - Wrapped check for value change inside ser_rd_overload_status > as suggested by Qais. > - Added reviewed-by tags. > > v1 -> v2: > - dropped Fixes tag. > - Added one of the perf probes in the changelog for reference. > - Added reviewed-by tags. > > tl;dr > When running workloads in large systems, it was observed that access to > rd->overload was taking time. It would be better to check the value > before updating since value changes less often. Patch 1/2 does that. > With patch updates happen only if necessary. CPU Bus traffic reduced a > bit. No significant gains in workload performance. Could you please post this against the latest scheduler tree, ie. tip:sched/core? Thanks, Ingo