Date:   Tue, 7 Feb 2023 09:30:45 -0800
From:   Josh Poimboeuf <jpoimboe@kernel.org>
To:     Thomas =?utf-8?Q?Wei=C3=9Fschuh?= <linux@weissschuh.net>
Cc:     Peter Zijlstra <peterz@infradead.org>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 0/8] objtool: reduce maximum memory usage
Message-ID: <20230207173045.ue77yxvp67p3hsrv@treble>
References: <20221216-objtool-memory-v2-0-17968f85a464@weissschuh.net>
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On Tue, Jan 31, 2023 at 09:27:15AM -0800, Josh Poimboeuf wrote:
> On Tue, Jan 31, 2023 at 03:54:42AM +0000, Thomas Weißschuh wrote:
> > On Mon, Jan 30, 2023 at 04:03:56PM -0800, Josh Poimboeuf wrote:
> > > On Sun, Jan 29, 2023 at 09:43:39PM +0000, Thomas Weißschuh wrote:
> > > > On Tue, Dec 27, 2022 at 04:00:57PM +0000, Thomas Weißschuh wrote:
> > > > > The processing of vmlinux.o with objtool is the most memory-intensive step
> > > > > of a kernel build. By reducing the maximum memory usage here we can reduce
> > > > > the maximum memory usage of the whole kernel build.
> > > > > Therefore memory pressure on memory starved machines is relieved during
> > > > > kernel builds and the build is faster as less swapping has to occur.
> > > > 
> > > > Friendly ping.
> > > > 
> > > > These patches can also applied one by one, the only dependency is from
> > > > patch 5 to patch 4.
> > > 
> > > Thanks, I'll go ahead and take five of them now.
> > 
> > Thanks.
> > 
> > I have another half-finished series that replaces the doubly-linked
> > list_heads used by elf.h with a custom singly-linked list.
> > This would save a few pointers per struct.
> > 
> > Do you think this is worth it?
> 
> Maybe, depending on the memory savings.

FYI, there were more memory usage complaints, so Peter worked up a nice
series to do this and more:

  https://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue.git/log/?h=objtool/core

-- 
Josh