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[141.239.158.86]) by smtp.gmail.com with ESMTPSA id i64-20020a62c143000000b006eadc37bad0sm1537852pfg.72.2024.03.28.13.46.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 28 Mar 2024 13:46:34 -0700 (PDT) Date: Thu, 28 Mar 2024 10:46:33 -1000 From: Tejun Heo To: Kent Overstreet Cc: Kemeng Shi , akpm@linux-foundation.org, willy@infradead.org, jack@suse.cz, bfoster@redhat.com, dsterba@suse.com, mjguzik@gmail.com, dhowells@redhat.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org Subject: Re: [PATCH v2 0/6] Improve visibility of writeback Message-ID: References: <20240327155751.3536-1-shikemeng@huaweicloud.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspam-User: X-Stat-Signature: byoo4fpcdjtp75p1ix77h363pq6ioes9 X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 4BBF714001D X-HE-Tag: 1711658796-807590 X-HE-Meta: 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 QB4tSsi9 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.042381, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Hello, Kent. On Thu, Mar 28, 2024 at 04:22:13PM -0400, Kent Overstreet wrote: > Most users are never going to touch tracing, let alone BPF; that's too > much setup. But I can and do regularly tell users "check this, this and > this" and debug things on that basis without ever touching their > machine. I think this is where the disconnect is. It's not difficult to set up at all. Nowadays, in most distros, it comes down to something like run "pacman -S bcc" and then run "/usr/share/bcc/tools/biolatpcts" with these params or run this script I'm attaching. It is a signficant boost when debugging many different kernel issues. I strongly suggest giving it a try and getting used to it rather than resisting it. Thanks. -- tejun