From mboxrd@z Thu Jan  1 00:00:00 1970
From: Yann E. MORIN <yann.morin.1998@free.fr>
Date: Wed, 8 Jun 2016 22:19:10 +0200
Subject: [Buildroot] [PATCH] package/systemd: Optionally disable hwdb
In-Reply-To: <1460717190-29291-1-git-send-email-m.niestroj@grinn-global.com>
References: <1460717190-29291-1-git-send-email-m.niestroj@grinn-global.com>
Message-ID: <20160608201910.GA3694@free.fr>
List-Id: <buildroot.busybox.net>
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
To: buildroot@busybox.net

Marcin, All,

On 2016-04-15 12:46 +0200, Marcin Niestroj spake thusly:
> By default hwdb files are installed in /usr/lib/udev/hwdb.d
> Currently they take about ~5MB. After first boot, systemd-hwdb tool
> parses them and creates a binary in /etc/udev/hwdb.bin, which takes
> another ~6.5MB.
> 
> In case of initramfs images, hwdb parsing is done every boot. This adds
> about 2-3 seconds to boot time in case of rootfs on SDHC class 10
> card (benchmarked with am335x board). NAND boot takes even longer.

So that's where my boot time goes! ;-)

> Add config option to disable hwdb in systemd, for smaller images and
> better boot performance.
> 
> Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>

I'm looking at all systemd-related pending patches, since I'm working on
cleaning up our systemd handling...

I have had a look at the systemd code to update the hwdb, and it is not
trivially replaced, so we would indeed need a host-systemd if we wanted
to generate the hwdb at build time.

I don't think this warrants the complexity of a host-systemd, however...

Yet, I'd like to know what would be the impact of not having hwdb
support at runtime. Care to shed some light, please?

Otherwise:

Reviewed-by: "Yann E. MORIN" <yann.morin.1998@free.fr>

Regards,
Yann E. MORIN.

> ---
>  package/systemd/Config.in  | 11 +++++++++++
>  package/systemd/systemd.mk |  6 ++++++
>  2 files changed, 17 insertions(+)
> 
> diff --git a/package/systemd/Config.in b/package/systemd/Config.in
> index 97d48c4..324e884 100644
> --- a/package/systemd/Config.in
> +++ b/package/systemd/Config.in
> @@ -84,6 +84,17 @@ config BR2_PACKAGE_SYSTEMD_JOURNAL_GATEWAY
>  
>  	  http://www.freedesktop.org/software/systemd/man/systemd-journal-gatewayd.service.html
>  
> +config BR2_PACKAGE_SYSTEMD_HWDB
> +	bool "enable hwdb installation"
> +	default y
> +	help
> +	  Enables hardware database installation to /usr/lib/udev/hwdb.d
> +
> +	  Disabling this option improves first boot time (or every boot
> +	  time in case of initramfs images) and saves several MB space.
> +
> +	  https://www.freedesktop.org/software/systemd/man/hwdb.html
> +
>  config BR2_PACKAGE_SYSTEMD_BINFMT
>  	bool "enable binfmt tool"
>  	help
> diff --git a/package/systemd/systemd.mk b/package/systemd/systemd.mk
> index 79e657e..29b62c0 100644
> --- a/package/systemd/systemd.mk
> +++ b/package/systemd/systemd.mk
> @@ -127,6 +127,12 @@ else
>  SYSTEMD_CONF_OPTS += --disable-microhttpd
>  endif
>  
> +ifeq ($(BR2_PACKAGE_SYSTEMD_HWDB),y)
> +SYSTEMD_CONF_OPTS += --enable-hwdb
> +else
> +SYSTEMD_CONF_OPTS += --disable-hwdb
> +endif
> +
>  ifeq ($(BR2_PACKAGE_SYSTEMD_BINFMT),y)
>  SYSTEMD_CONF_OPTS += --enable-binfmt
>  else
> -- 
> 2.8.0
> 
> _______________________________________________
> buildroot mailing list
> buildroot at busybox.net
> http://lists.busybox.net/mailman/listinfo/buildroot

-- 
.-----------------.--------------------.------------------.--------------------.
|  Yann E. MORIN  | Real-Time Embedded | /"\ ASCII RIBBON | Erics' conspiracy: |
| +33 662 376 056 | Software  Designer | \ / CAMPAIGN     |  ___               |
| +33 223 225 172 `------------.-------:  X  AGAINST      |  \e/  There is no  |
| http://ymorin.is-a-geek.org/ | _/*\_ | / \ HTML MAIL    |   v   conspiracy.  |
'------------------------------^-------^------------------^--------------------'