[PATCH] Fix the smb.conf for aio read/write size

[Jeremy Allison]

On Mon, Nov 20, 2017 at 05:19:55PM +0100, Volker Lendecke via samba-technical wrote:
> Hi!
> 
> Review appreciated!
> 
> Thanks, Volker

LGTM. Pushed !

> SerNet GmbH, Bahnhofsallee 1b, 37081 Göttingen
> phone: +49-551-370000-0, fax: +49-551-370000-9
> AG Göttingen, HRB 2816, GF: Dr. Johannes Loxen
> http://www.sernet.de, mailto:kontakt at sernet.de

> From de275a23bbf3eb70cae7e4d79a7c75cb61db8065 Mon Sep 17 00:00:00 2001
> From: Volker Lendecke <vl at samba.org>
> Date: Mon, 20 Nov 2017 17:18:44 +0100
> Subject: [PATCH] docs: Fix the "aio r/w size" smb.conf entries
> 
> Signed-off-by: Volker Lendecke <vl at samba.org>
> ---
>  docs-xml/smbdotconf/tuning/aioreadsize.xml  | 15 ++++++---------
>  docs-xml/smbdotconf/tuning/aiowritesize.xml | 18 ++++++++++--------
>  2 files changed, 16 insertions(+), 17 deletions(-)
> 
> diff --git a/docs-xml/smbdotconf/tuning/aioreadsize.xml b/docs-xml/smbdotconf/tuning/aioreadsize.xml
> index 0c9cc529ed8..c6028b8f9ac 100644
> --- a/docs-xml/smbdotconf/tuning/aioreadsize.xml
> +++ b/docs-xml/smbdotconf/tuning/aioreadsize.xml
> @@ -3,20 +3,17 @@
>                   type="bytes"
>                   xmlns:samba="http://www.samba.org/samba/DTD/samba-doc">
>  <description>
> -  <para>If Samba has been built with asynchronous I/O support and this
> -    integer parameter is set to non-zero value,
> -    Samba will read from file asynchronously when size of request is bigger
> +  <para>If this integer parameter is set to a non-zero value,
> +    Samba will read from files asynchronously when the request size is bigger
>      than this value. Note that it happens only for non-chained and non-chaining
>      reads and when not using write cache.</para>
> -
> -  <para>Current implementation of asynchronous I/O in Samba 3.0 does support
> -    only up to 10 outstanding asynchronous requests, read and write combined.</para>
> -
> +  <para>The only reasonable values for this parameter are 0 (no async I/O) and
> +    1 (always do async I/O).</para>
>    <related>write cache size</related>
>    <related>aio write size</related>
>  </description>
>  
>  <value type="default">0</value>
> -<value type="example">16384<comment> Use asynchronous I/O for reads bigger than 16KB
> -    request size</comment></value>
> +<value type="example">1<comment>Always do reads asynchronously
> +  </comment></value>
>  </samba:parameter>
> diff --git a/docs-xml/smbdotconf/tuning/aiowritesize.xml b/docs-xml/smbdotconf/tuning/aiowritesize.xml
> index c2ad118def0..8f42284111e 100644
> --- a/docs-xml/smbdotconf/tuning/aiowritesize.xml
> +++ b/docs-xml/smbdotconf/tuning/aiowritesize.xml
> @@ -3,20 +3,22 @@
>                   type="bytes"
>                   xmlns:samba="http://www.samba.org/samba/DTD/samba-doc">
>  <description>
> -  <para>If Samba has been built with asynchronous I/O support and this
> -    integer parameter is set to non-zero value,
> -    Samba will write to file asynchronously when size of request is bigger
> +  <para>If this integer parameter is set to a non-zero value,
> +    Samba will write to files asynchronously when the request size is bigger
>      than this value. Note that it happens only for non-chained and non-chaining
>      reads and when not using write cache.</para>
> -
> -  <para>Current implementation of asynchronous I/O in Samba 3.0 does support
> -    only up to 10 outstanding asynchronous requests, read and write combined.</para>
> +  <para>The only reasonable values for this parameter are 0 (no async I/O) and
> +    1 (always do async I/O).</para>
> +  <para>Compared to <smbconfoption name="aio read size"/> this parameter has
> +    a smaller effect, most writes should end up in the
> +    file system cache. Writes that require space allocation might
> +    benefit most from going asynchronous.</para>
>    
>    <related>write cache size</related>
>    <related>aio read size</related>
>  </description>
>  
>  <value type="default">0</value>
> -<value type="example">16384<comment> Use asynchronous I/O for writes bigger than 16KB
> -    request size</comment></value>
> +<value type="example">1<comment>Always do writes asynchronously
> +    </comment></value>
>  </samba:parameter>
> -- 
> 2.11.0
>