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Date:   Wed, 22 May 2019 18:00:47 -0700 (PDT)
Message-Id: <20190522.180047.238715219030499893.davem@davemloft.net>
To:     sunilmut@microsoft.com
Cc:     kys@microsoft.com, haiyangz@microsoft.com, sthemmin@microsoft.com,
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        linux-kernel@vger.kernel.org
Subject: Re: [PATCH net-next] hv_sock: perf: Allow the socket buffer size
 options to influence the actual socket buffers
From:   David Miller <davem@davemloft.net>
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From: Sunil Muthuswamy <sunilmut@microsoft.com>
Date: Wed, 22 May 2019 22:56:07 +0000

> Currently, the hv_sock buffer size is static and can't scale to the
> bandwidth requirements of the application. This change allows the
> applications to influence the socket buffer sizes using the SO_SNDBUF and
> the SO_RCVBUF socket options.
> 
> Few interesting points to note:
> 1. Since the VMBUS does not allow a resize operation of the ring size, the
> socket buffer size option should be set prior to establishing the
> connection for it to take effect.
> 2. Setting the socket option comes with the cost of that much memory being
> reserved/allocated by the kernel, for the lifetime of the connection.
> 
> Perf data:
> Total Data Transfer: 1GB
> Single threaded reader/writer
> Results below are summarized over 10 iterations.
 ...
> Signed-off-by: Sunil Muthuswamy <sunilmut@microsoft.com>

Applied.