I'm back on my "build machine" taking a look at what impact make-4.0 is likely to have. I got this machine nearly 18 months ago (AMD phenom, 4 real CPUs, 8GB of memory less the built-in graphics) and at that time it had a habit of losing its lunch [ Interal Compiler Errors ] if I ran make -j4 (kernel compiles almost always ok but other things tended to fall flat on their face), so that I had to drop the caches and limit myself to 3 jobs.
Also, at some point the kernel cpufreq for the phenom changed to acpi and it took me a while to tune my initscript so that it was again faster than my intel SandyBridge. But earlier this year things were looking good and I was able to use make -j4 without worrying. Now, I'm building *from* LFS-7.4. Wednesday I was building last month's LFS-svn (my error, I apparently updated my repo without rebuilding the local copy of the book) on linux-3.11.1 with make-4.0. Perhaps 3.11.1 was a bad kernel, but things fell over with ICEs in chroot and I had to drop back to make -j3, and then at the end of chapter 6 (when I realised I was using an out of date set of packages) I got a segfault unmounting /mnt/lfs and lost the box when I tried to drop back to a tty. Turned out one of the ICE segfaults was associated with a bad page table, and the box had BUG:'d. Thursday, I've built 3.11.4 (hopefully, better - no bugs or oopses in the kernel logs so far) but I've still had to drop back to make -j3 in chroot because of ICEs. Also had an ICE with Python-2.7.5 (one of the things I build before booting) and make -j3, but that completed ok after I dropped the caches and retried. Now that it has booted, it seems to be ok. I'm still running with make -j4 for the moment. But what really concerns me is the SBU time: the only real changes since LFS-7.4 are make-4.0 and gmp-5.1.3. One of the things I normally do in a new system is to rerun binutils pass 1 [ -j1 ] so that I can recalculate the SBU [ building from an old system will always be quicker ]. On 7.4 it built itself in 208.542 seconds. For this build, binutils pass 1 took 156.559 seconds (seems unrealistically quick) but rebuilding itself after booting took 253.243 seconds which is a lot longer than I was expecting. I saw that mandb was running for some minutes after I booted, but with 4 CPUs and nearly 8GB of RAM that didn't ought to make a lot of difference to the timings. Is it just me and my not quite as good as expected hardware, or are things getting flakey ? ĸen -- das eine Mal als Tragödie, dieses Mal als Farce -- http://linuxfromscratch.org/mailman/listinfo/lfs-chat FAQ: http://www.linuxfromscratch.org/faq/ Unsubscribe: See the above information page
