From: Christoph Hellwig <hch@infradead.org>
To: Vishnu ks <ksvishnu56@gmail.com>
Cc: Song Liu <song@kernel.org>,
hch@infradead.org, yanjun.zhu@linux.dev,
lsf-pc@lists.linux-foundation.org, linux-block@vger.kernel.org,
bpf@vger.kernel.org, linux-nvme@lists.infradead.org
Subject: Re: [LSF/MM/BPF TOPIC] Improving Block Layer Tracepoints for Next-Generation Backup Systems
Date: Sun, 5 Jan 2025 23:37:28 -0800 [thread overview]
Message-ID: <Z3uIOPxr4s09qS1X@infradead.org> (raw)
In-Reply-To: <CAJHDoJYESDzDf9KJgfSfGGit6JPyxtf3miNbnM7BzNfjOi7CQw@mail.gmail.com>
On Sat, Jan 04, 2025 at 11:22:40PM +0530, Vishnu ks wrote:
> 1. Uses eBPF to monitor block_rq_complete tracepoint to track modified sectors
You can't. Drivers can and often do change the sector during submission
processing.
> 2. Captures sector numbers (not data) of changed blocks in real-time
> 3. Periodically syncs the actual data from these sectors based on
> configurable RPO
> 4. Layers these incremental changes on top of base snapshots
And all of that is broken. If you are interested in this kind of
mechanism help upstreaming the blk-filter work, which has been
explicitly designed to support that.
Before that you should really undestand how block devices and
file systems work, as the rest of the mail suggested a very dangerous
misunderstanding of the basic principles.
next prev parent reply other threads:[~2025-01-06 7:37 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-01-01 6:34 [LSF/MM/BPF TOPIC] Improving Block Layer Tracepoints for Next-Generation Backup Systems Vishnu ks
2025-01-03 9:26 ` Christoph Hellwig
2025-01-04 0:47 ` Zhu Yanjun
2025-01-04 1:11 ` Song Liu
2025-01-04 17:52 ` Vishnu ks
2025-01-06 1:53 ` Damien Le Moal
2025-01-06 18:28 ` Vishnu ks
2025-01-06 7:37 ` Christoph Hellwig [this message]
2025-01-06 14:39 ` Zhu Yanjun
2025-01-06 18:36 ` Vishnu ks
2025-01-06 18:31 ` Vishnu ks
2025-01-06 21:19 ` Song Liu
2025-01-06 22:18 ` [Lsf-pc] " Dan Williams
2025-01-13 17:31 ` Vishnu ks
2025-02-07 2:06 ` Ming Lei
2025-02-07 11:15 ` Vishnu ks
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