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Date: Wed, 3 Apr 2024 18:27:16 +0200
From: Jan Kara <jack@suse.cz>
To: Tejun Heo <tj@kernel.org>
Cc: Kent Overstreet <kent.overstreet@linux.dev>,
	Kemeng Shi <shikemeng@huaweicloud.com>, 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
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On Thu 28-03-24 10:46:33, Tejun Heo wrote:
> 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.

Yeah, BPF is great and I use it but to fill in some cases from practice,
there are sysadmins refusing to install bcc or run your BPF scripts on
their systems due to company regulations, their personal fear, or whatever.
So debugging with what you can achieve from a shell is still the thing
quite often.

								Honza
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR