Date: Mon, 2 Dec 2019 14:11:17 -0800 From: Mark Millard <marklmi@yahoo.com> To: bob prohaska <fbsd@www.zefox.net> Cc: freebsd-arm@freebsd.org Subject: Re: Reverting -current by date. Message-ID: <49C39BF2-0F0A-4D79-831C-89A6F853874B@yahoo.com> In-Reply-To: <20191201213920.GA49395@www.zefox.net> References: <20191120233653.GA1475@www.zefox.net> <CF0E4D8C-835C-42A7-B778-7899E779FB19@yahoo.com> <20191121031141.GB1837@www.zefox.net> <E752E69D-814C-4182-A2AC-EA15FF69A7B6@yahoo.com> <20191121175817.GA5375@www.zefox.net> <DC498AB2-BCAC-4133-9789-7DFCCF7F928F@yahoo.com> <20191121190903.GB5375@www.zefox.net> <EAC55963-5220-4EA4-87F8-4752BF89CB4F@yahoo.com> <20191126010310.GA26370@www.zefox.net> <254A5077-DE9E-4B6A-9A4D-D9FA2F858F54@yahoo.com> <20191201213920.GA49395@www.zefox.net>
next in thread | previous in thread | raw e-mail | index | archive | help
On 2019-Dec-1, at 13:39, bob prohaska <fbsd@www.zefox.net> wrote: > On Mon, Nov 25, 2019 at 05:52:02PM -0800, Mark Millard wrote: >> >> >> >> FYI, one contributor to from-scratch build times might be >> the update to llvm 9: >> >> QUOTE >> Revision 353358 - (view) (download) (annotate) - [select for diffs] >> Modified Wed Oct 9 17:06:56 2019 UTC (6 weeks, 5 days ago) by dim >> File length: 12392 byte(s) >> Diff to previous 353274 >> Merge llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and openmp >> 9.0.0 final release >> r372316 >> . >> >> Release notes for llvm, clang, lld and libc++ 9.0.0 are available here: >> >> >> https://releases.llvm.org/9.0.0/docs/ReleaseNotes.html >> https://releases.llvm.org/9.0.0/tools/clang/docs/ReleaseNotes.html >> https://releases.llvm.org/9.0.0/tools/lld/docs/ReleaseNotes.html >> https://releases.llvm.org/9.0.0/projects/libcxx/docs/ReleaseNotes.html >> >> >> PR: 240629 >> MFC after: 1 month >> END QUOTE >> >> I do not know if you do anything to limit what is built relative to >> llvm or not. (I do not remember the defaults or the minimums.) >> >> Are your from-scratch rebuilds building both a bootstrap llvm9 and >> the normal llvm9? Or is the existing llvm9 used instead of making >> a bootstrap build of llvm9? >> >> Any llvm8->llvm9 transition will get the bootstrap build of llvm9, >> which then will be used for the later stages. >> > > I think the transition is complete at this point, with clang60 through > clang80 resident in /usr/local/bin and clang9 being default. > > Is there any reason to think clang9 is substantially slower or more > resource-intensive than clang 8? My intended context here was buildworld (and buildkernel), not port building. There can be a big difference here for 2 aspects: A) Building the (ever larger) llvm materials B) General rate at which the llvm tool chain processes things or the sizes for the RAM use It is (A) that I was thinking of: the llvm9 materials to be built may be more time consuming to build. Building llvm materials takes a sizable part of the total buildworld time last I checked. This can be true even if the rates in (B) have improved. (I've no clue if any have.) > if so, that, that would at least > contribute to the difficulties I'm observing (along with tired flash > devices). Last time the machine successfully compiled www/chromium > it took about 3.5 GB of swap at peak. Recent attempts, even with > -j2, are approaching 4 GB and failing with random kernel panics. As for ports (other than llvm* ones) . . . Clearly (B) above is involved but I've no general specifics. I am not aware of a way to set up for port builds that use lld to automatically use --no-threads . (But I've no clue if link-time via lld is one of your large swap usage points --or, if it is, if this would be enough to help.) For buildworld buildkernel there is a way. The binutils ld does not support --no-threads as a command line option last I checked, not even as an ignored compatibility option. Thus adding the option to all link activity is not a working alternative. I do not know if your -j2 is with or without MAKE_JOBS being enabled for some or all jobs. === Mark Millard marklmi at yahoo.com ( dsl-only.net went away in early 2018-Mar)
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?49C39BF2-0F0A-4D79-831C-89A6F853874B>