From: Christoph Hellwig <hch@infradead.org>
To: Sumit Saxena <sumit.saxena@broadcom.com>
Cc: "Martin K . Petersen" <martin.petersen@oracle.com>,
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Bart Van Assche <bvanassche@acm.org>
Subject: Re: [PATCH v3 3/4] block: drop shared-tag fairness throttling
Date: Tue, 9 Jun 2026 23:14:11 -0700 [thread overview]
Message-ID: <aikAs4X-2NWTuwCc@infradead.org> (raw)
In-Reply-To: <20260609121806.2121755-4-sumit.saxena@broadcom.com>
Just dropping the fairness was rejected before and there is no
explanation here on why any of that has changed.
On Tue, Jun 09, 2026 at 05:48:02PM +0530, Sumit Saxena wrote:
> From: Bart Van Assche <bvanassche@acm.org>
>
> Original patch [1] by Bart Van Assche; this version is rebased onto the
> current tree. In testing it improves IOPS by roughly 16-18% by removing
> the fair-sharing throttle on shared tag queues.
>
> This patch removes the following code and structure members:
> - The function hctx_may_queue().
> - blk_mq_hw_ctx.nr_active and request_queue.nr_active_requests_shared_tags
> and also all the code that modifies these two member variables.
.. and besides that, this commit message is still entirely useless
as it doesn't explain any of the thoughts of why this change is safe
and desirable. While the mechanics above are totally obvious from
the code change itself.
next prev parent reply other threads:[~2026-06-10 6:15 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-06-09 12:17 [PATCH v3 0/4] scsi/block: NUMA-local scan allocations, shared-tag path cleanup, and SCSI I/O counters Sumit Saxena
2026-06-09 12:18 ` [PATCH v3 1/4] scsi: scan: allocate sdev and starget on the NUMA node of the host adapter Sumit Saxena
2026-06-10 6:00 ` Hannes Reinecke
2026-06-09 12:18 ` [PATCH v3 2/4] scsi: host: allocate struct Scsi_Host " Sumit Saxena
2026-06-09 13:03 ` John Garry
2026-06-10 5:59 ` Hannes Reinecke
2026-06-09 12:18 ` [PATCH v3 3/4] block: drop shared-tag fairness throttling Sumit Saxena
2026-06-10 6:14 ` Christoph Hellwig [this message]
[not found] ` <CAL2rwxr1uGshb1o=jvP2OnBffNz2cKXj8tHuAUCN5HFuy2vB_g@mail.gmail.com>
2026-06-10 16:35 ` Keith Busch
2026-06-10 6:18 ` Hannes Reinecke
2026-06-09 12:18 ` [PATCH v3 4/4] scsi: use percpu counters for iostat counters in struct scsi_device Sumit Saxena
2026-06-10 6:21 ` Hannes Reinecke
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