From mboxrd@z Thu Jan 1 00:00:00 1970 From: Harald Hoyer Subject: Re: building initramfs is slow Date: Fri, 19 Aug 2011 09:03:32 +0200 Message-ID: <4E4E0AC4.1020709@redhat.com> References: <4E4D5779.6090209@bitwagon.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4E4D5779.6090209-Po6cBsTGB2ZWk0Htik3J/w@public.gmane.org> Sender: initramfs-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: text/plain; charset="us-ascii" To: John Reiser Cc: initramfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org On 18.08.2011 20:18, John Reiser wrote: > Building an initramfs is unreasonably slow. On Fedora 16 > dracut-011 takes almost a minute when installing a new kernel: > real 56s > user 20s \__ dracut is CPU bound, not I/O bound. > sys 31s / > The final "gzip -9" takes 12 seconds, and the cpio 1 second, > which leaves 43 seconds for the rest of dracut. That's a > factor of 3 or 4 too long. The output initramfs is 14.9MB > (41MB unzipped) and contains 1619 files, including 367 .ko > kernel modules. Some general thoughts. 1. speed at initramfs creation time is not sooo important. Normally this is only done once in a while and not every day. Boot speed is more important. 2. if you care about speed of creation and size of the initramfs, turn on "hostonly" in /etc/dracut.conf > Yes, I'm going to work on it. > That's cool! I accept patches :-)