Received-SPF: pass (google.com: best guess record for domain of linux-nfs-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
To:     linux-nfs@vger.kernel.org
From:   Alkis Georgopoulos <alkisg@gmail.com>
Subject: rsize,wsize=1M causes severe lags in 10/100 Mbps, what sets those
 defaults?
Message-ID: <80353d78-e3d9-0ee2-64a4-cd2f22272fbe@gmail.com>
Date:   Thu, 19 Sep 2019 10:29:40 +0300
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101
 Thunderbird/60.8.0
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Sender: linux-nfs-owner@vger.kernel.org
Precedence: bulk

Hi, in any recent distribution that I tried, the default NFS wsize/rsize 
was 1 MB.

On 10/100 Mbps networks, this causes severe lags, timeouts, and dmesg 
fills with messages like:

 > [  316.404250] nfs: server 192.168.1.112 not responding, still trying
 > [  316.759512] nfs: server 192.168.1.112 OK

Forcing wsize/rsize to 32K makes all the problems disappear and NFS 
access more snappy, without sacrificing any speed at least up to gigabit 
networks that I tested with.

I would like to request that the defaults be changed to 32K.
But I didn't find out where these defaults come from, where to file the 
issue and my test case / benchmarks to support it.

I've initially reported it at the klibc nfsmount program that I was 
using, but this is just using the NFS defaults, which are the ones that 
should be amended. So initial test case / benchmarks there:
https://lists.zytor.com/archives/klibc/2019-September/004234.html

Please Cc me as I'm not in the list.

Thank you,
Alkis Georgopoulos