From: Michael Opdenacker <michael.opdenacker@free-electrons.com>
To: akpm@linux-foundation.org
Cc: paulmck@linux.vnet.ibm.com, fweisbec@gmail.com,
josh@joshtriplett.org, eparis@redhat.com,
paul.gortmaker@windriver.com, vapier@gentoo.org,
kyungsik.lee@lge.com, jslaby@suse.cz, dwight.engen@oracle.com,
pefoley2@pefoley.com, linux-kernel@vger.kernel.org,
Michael Opdenacker <michael.opdenacker@free-electrons.com>
Subject: [PATCH 1/1] init/Kconfig: improve CC_OPTIMIZE_FOR_SIZE documentation
Date: Thu, 24 Apr 2014 14:07:34 +0200 [thread overview]
Message-ID: <1398341254-4626-2-git-send-email-michael.opdenacker@free-electrons.com> (raw)
In-Reply-To: <1398341254-4626-1-git-send-email-michael.opdenacker@free-electrons.com>
Signed-off-by: Michael Opdenacker <michael.opdenacker@free-electrons.com>
---
init/Kconfig | 14 +++++++++++++-
1 file changed, 13 insertions(+), 1 deletion(-)
diff --git a/init/Kconfig b/init/Kconfig
index 9d3585bb2a7a..b6394a9ddc38 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -1251,7 +1251,19 @@ config CC_OPTIMIZE_FOR_SIZE
bool "Optimize for size"
help
Enabling this option will pass "-Os" instead of "-O2" to gcc
- resulting in a smaller kernel.
+ resulting in a smaller but slower kernel.
+
+ This option can be useful in very small systems where every
+ byte counts.
+
+ A smaller kernel will also be slightly faster to load and start.
+ However, experiments have shown that such early speedups are
+ quickly offset by the slower kernel speed. Unless you are running
+ a very simple user space, the total boot time should be degraded
+ by this option.
+
+ Anyway, kernel code will be slower to execute and overall system
+ performance will be degraded.
If unsure, say N.
--
1.8.3.2
next prev parent reply other threads:[~2014-04-24 12:08 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-04-24 12:07 [PATCH 0/1] " Michael Opdenacker
2014-04-24 12:07 ` Michael Opdenacker [this message]
2014-04-24 15:06 ` [PATCH 1/1] " Josh Triplett
2014-04-24 14:55 ` [PATCH 0/1] " Josh Triplett
2014-04-24 19:34 ` Michael Opdenacker
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1398341254-4626-2-git-send-email-michael.opdenacker@free-electrons.com \
--to=michael.opdenacker@free-electrons.com \
--cc=akpm@linux-foundation.org \
--cc=dwight.engen@oracle.com \
--cc=eparis@redhat.com \
--cc=fweisbec@gmail.com \
--cc=josh@joshtriplett.org \
--cc=jslaby@suse.cz \
--cc=kyungsik.lee@lge.com \
--cc=linux-kernel@vger.kernel.org \
--cc=paul.gortmaker@windriver.com \
--cc=paulmck@linux.vnet.ibm.com \
--cc=pefoley2@pefoley.com \
--cc=vapier@gentoo.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®