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AJvYcCX94mXRtIVToq+e3BNd5DQBGXzkAjunZXyBsnfHUW97bfnqRCSIbn+PVInsADxMjNUWbyO7jufSGa5f9k628k6zdsZUZ6yRcFnVGOw= X-Gm-Message-State: AOJu0Yy4T2HozyVGqt2Nwbj7j/9DXYziCXKDCJLAdePS3Pkkq/17w/2O ScQPOD08C+WR42qGSinbTA/kGy3MthMlnycMpK43DR0o8Dz5TnZ+HjLstfuE5LX78ksY9JPMR7r MFfk= X-Google-Smtp-Source: AGHT+IHOrHK0Rz6XvUsgTR5CvGlJIHipE73E1BMvd4gM2EgON8ff++cWGZ67lwjV8sKJ4DV1NZE5Jw== X-Received: by 2002:a05:6871:3324:b0:259:862f:b898 with SMTP id 586e51a60fabf-25cf03e224fmr19822041fac.5.1719608119266; Fri, 28 Jun 2024 13:55:19 -0700 (PDT) Received: from [127.0.0.1] ([96.43.243.2]) by smtp.gmail.com with ESMTPSA id 586e51a60fabf-25d8e37ee64sm595605fac.47.2024.06.28.13.55.18 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 28 Jun 2024 13:55:18 -0700 (PDT) From: Jens Axboe To: tj@kernel.org, josef@toxicpanda.com, Yu Kuai Cc: cgroups@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, yukuai3@huawei.com, yi.zhang@huawei.com, yangerkun@huawei.com In-Reply-To: <20240618062108.3680835-1-yukuai1@huaweicloud.com> References: <20240618062108.3680835-1-yukuai1@huaweicloud.com> Subject: Re: [PATCH v2] blk-throttle: fix lower control under super low iops limit Message-Id: <171960811810.898565.9691388431635837442.b4-ty@kernel.dk> Date: Fri, 28 Jun 2024 14:55:18 -0600 Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Mailer: b4 0.14.0 On Tue, 18 Jun 2024 14:21:08 +0800, Yu Kuai wrote: > User will configure allowed iops limit in 1s, and calculate_io_allowed() > will calculate allowed iops in the slice by: > > limit * HZ / throtl_slice > > However, if limit is quite low, the result can be 0, then > allowed IO in the slice is 0, this will cause missing dispatch and > control will be lower than limit. > > [...] Applied, thanks! [1/1] blk-throttle: fix lower control under super low iops limit commit: 1beabab88ecee0698ecee7b54afa9cce7046ef96 Best regards, -- Jens Axboe