<div><div dir="auto">Tom,</div></div><div dir="auto">Then what ratio do you think it’s minimal?</div><div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Thu, Apr 2, 2020 at 6:11 Tom Stellard <<a href="mailto:tstellar@redhat.com">tstellar@redhat.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">On 04/01/2020 01:47 PM, Itaru Kitayama via llvm-dev wrote:<br>
> Thanks for the heads up the supercomputer <br>
> Is down for maintenance this week.<br>
> I’ll give it a try when it gets back.<br>
> <br>
<br>
This doesn't look to me like it's necessarily an lld issue. Trying<br>
to build all the sub-projects without limiting the number of ninja jobs<br>
is almost guaranteed to run out of memory on a machine like this with such<br>
a low memory:core ratio.<br>
<br>
-Tom<br>
<br>
> On Thu, Apr 2, 2020 at 1:49 Fangrui Song <<a href="mailto:maskray@google.com" target="_blank">maskray@google.com</a> <mailto:<a href="mailto:maskray@google.com" target="_blank">maskray@google.com</a>>> wrote:<br>
> <br>
> On 2020-03-29, Nemanja Ivanovic via llvm-dev wrote:<br>
> >Glad you got it working.<br>
> >My suggestion about LLVM_ENABLE_THREADS didn't work because you didn't<br>
> >apply it when building the build linker.<br>
> ><br>
> >When you don't have the ability to rebuild the build compiler, this doesn't<br>
> >apply. In those cases, I end up doing a dirty hack where I use a wrapper<br>
> >script with something like:<br>
> ><br>
> ><path-to-build-compiler> "$@" -Wl,--no-threads<br>
> ><br>
> >To invoke the build compiler. That way you still get full parallelism while<br>
> >compiling and linking, but you prevent LLD from using threads.<br>
> <br>
> <br>
> <a href="https://reviews.llvm.org/D76885" rel="noreferrer" target="_blank">https://reviews.llvm.org/D76885</a> (committed yesterday) changed<br>
> --no-threads to --threads={1,2,...} (--no-threads is used rarely (GNU ld<br>
> does not support it) so I'd rather not keep the option for<br>
> compatibility).<br>
> <br>
> You may try -Wl,--threads=1<br>
> <br>
> >On Sat., Mar. 28, 2020, 4:19 p.m. Itaru Kitayama, <<a href="mailto:itaru.kitayama@gmail.com" target="_blank">itaru.kitayama@gmail.com</a> <mailto:<a href="mailto:itaru.kitayama@gmail.com" target="_blank">itaru.kitayama@gmail.com</a>>><br>
> >wrote:<br>
> ><br>
> >> Good news, I was able to use up to 37 cores for LLVM build with LLD.<br>
> >> The build speed, did not measure precisely though, is comparable to the<br>
> >> build with GNU ld case.<br>
> >><br>
> >> Thank you all for your help!<br>
> >><br>
> >> On Sun, Mar 29, 2020 at 5:04 AM Alex Brachet-Mialot <<br>
> >> <a href="mailto:alexbrachetmialot@gmail.com" target="_blank">alexbrachetmialot@gmail.com</a> <mailto:<a href="mailto:alexbrachetmialot@gmail.com" target="_blank">alexbrachetmialot@gmail.com</a>>> wrote:<br>
> >><br>
> >>> Yes unfortunately that would limit you to 4 cores.<br>
> >>><br>
> >>> There’s no easy way to use lld with —no-threads with our build system at<br>
> >>> the moment unfortunately.<br>
> >>><br>
> >>> I also had just been using ld.gold, but will switch now that numactl<br>
> >>> works for me.<br>
> >>><br>
> >>> On Sat, Mar 28, 2020 at 3:58 PM Itaru Kitayama <<a href="mailto:itaru.kitayama@gmail.com" target="_blank">itaru.kitayama@gmail.com</a> <mailto:<a href="mailto:itaru.kitayama@gmail.com" target="_blank">itaru.kitayama@gmail.com</a>>><br>
> >>> wrote:<br>
> >>><br>
> >>>> That is slowing down the build visibly, for the speed I should stick<br>
> >>>> with ld at the moment.<br>
> >>>><br>
> >>>><br>
> >>>> On Sun, Mar 29, 2020 at 4:42 AM Alexandre Ganea <<br>
> >>>> <a href="mailto:alexandre.ganea@ubisoft.com" target="_blank">alexandre.ganea@ubisoft.com</a> <mailto:<a href="mailto:alexandre.ganea@ubisoft.com" target="_blank">alexandre.ganea@ubisoft.com</a>>> wrote:<br>
> >>>><br>
> >>>>> Would `taskset -c 0-3 ninja check-all -j4` work?<br>
> >>>>><br>
> >>>>><br>
> >>>>><br>
> >>>>> *De :* Itaru Kitayama <<a href="mailto:itaru.kitayama@gmail.com" target="_blank">itaru.kitayama@gmail.com</a> <mailto:<a href="mailto:itaru.kitayama@gmail.com" target="_blank">itaru.kitayama@gmail.com</a>>><br>
> >>>>> *Envoyé :* March 28, 2020 3:37 PM<br>
> >>>>> *À :* Alex Brachet-Mialot <<a href="mailto:alexbrachetmialot@gmail.com" target="_blank">alexbrachetmialot@gmail.com</a> <mailto:<a href="mailto:alexbrachetmialot@gmail.com" target="_blank">alexbrachetmialot@gmail.com</a>>><br>
> >>>>> *Cc :* Alexandre Ganea <<a href="mailto:alexandre.ganea@ubisoft.com" target="_blank">alexandre.ganea@ubisoft.com</a> <mailto:<a href="mailto:alexandre.ganea@ubisoft.com" target="_blank">alexandre.ganea@ubisoft.com</a>>>; LLVM Dev <<br>
> >>>>> <a href="mailto:llvm-dev@lists.llvm.org" target="_blank">llvm-dev@lists.llvm.org</a> <mailto:<a href="mailto:llvm-dev@lists.llvm.org" target="_blank">llvm-dev@lists.llvm.org</a>>>; Nemanja Ivanovic <<a href="mailto:nemanja.i.ibm@gmail.com" target="_blank">nemanja.i.ibm@gmail.com</a> <mailto:<a href="mailto:nemanja.i.ibm@gmail.com" target="_blank">nemanja.i.ibm@gmail.com</a>>><br>
> >>>>> *Objet :* Re: [llvm-dev] LLD issue on a massively parallel build<br>
> >>>>> machine<br>
> >>>>><br>
> >>>>><br>
> >>>>><br>
> >>>>> $ free -g<br>
> >>>>> total used free shared buff/cache<br>
> >>>>> available<br>
> >>>>> Mem: 376 149 20 1 207<br>
> >>>>> 225<br>
> >>>>> Swap: 3 0 3<br>
> >>>>><br>
> >>>>><br>
> >>>>><br>
> >>>>> Too small swap size for a 72-core login machine?<br>
> >>>>><br>
> >>>>><br>
> >>>>><br>
> >>>>> On Sun, Mar 29, 2020 at 4:28 AM Alex Brachet-Mialot <<br>
> >>>>> <a href="mailto:alexbrachetmialot@gmail.com" target="_blank">alexbrachetmialot@gmail.com</a> <mailto:<a href="mailto:alexbrachetmialot@gmail.com" target="_blank">alexbrachetmialot@gmail.com</a>>> wrote:<br>
> >>>>><br>
> >>>>> Enable threads is for building llvm with or without thread support. To<br>
> >>>>> my knowledge it has no effect on the build system.<br>
> >>>>><br>
> >>>>><br>
> >>>>><br>
> >>>>> Like was discussed above you could try limiting the number of<br>
> >>>>> processes created (assuming your lld was after that commit) with numactl or<br>
> >>>>> taskset.<br>
> >>>>><br>
> >>>>><br>
> >>>>><br>
> >>>>> In your case though it looked like you were running out of memory. You<br>
> >>>>> could try increasing your swap space?<br>
> >>>>><br>
> >>>>><br>
> >>>>><br>
> >>>>> Alex<br>
> >>>>><br>
> >>>>><br>
> >>>>><br>
> >>>>> On Sat, Mar 28, 2020 at 3:15 PM Itaru Kitayama <<br>
> >>>>> <a href="mailto:itaru.kitayama@gmail.com" target="_blank">itaru.kitayama@gmail.com</a> <mailto:<a href="mailto:itaru.kitayama@gmail.com" target="_blank">itaru.kitayama@gmail.com</a>>> wrote:<br>
> >>>>><br>
> >>>>> Hi,<br>
> >>>>><br>
> >>>>> My configuration is below:<br>
> >>>>><br>
> >>>>> cmake -GNinja -DLLVM_ENABLE_LLD=ON -DLLVM_ENABLE_THREADS=OFF<br>
> >>>>> -DLLVM_ENABLE_LIBCXX=ON -DCMAKE_BUILD_TYPE=Release<br>
> >>>>> -DGCC_INSTALL_PREFIX=/home/usr4/c74014i/opt/gcc-7.5.0/<br>
> >>>>> -DLIBOMPTARGET_ENABLE_DEBUG=ON<br>
> >>>>> -DCMAKE_INSTALL_PREFIX=$HOME/opt/clang/${today} -DCMAKE_C_COMPILER=clang<br>
> >>>>> -DCMAKE_C_FLAGS="" -DCMAKE_CXX_COMPILER=clang++ -DCMAKE_CXX_FLAGS=""<br>
> >>>>> -DLLVM_ENABLE_PROJECTS="clang;openmp;lld;libcxx;libcxxabi;compiler-rt;libunwind"<br>
> >>>>> -DCLANG_OPENMP_NVPTX_DEFAULT_ARCH=sm_60<br>
> >>>>> -DLIBOMPTARGET_NVPTX_COMPUTE_CAPABILITIES=60 -DLLVM_TARGETS_TO_BUILD="all"<br>
> >>>>> /tmp/llvm-project/llvm<br>
> >>>>><br>
> >>>>><br>
> >>>>><br>
> >>>>> but did not help my case:<br>
> >>>>><br>
> >>>>><br>
> >>>>><br>
> >>>>> [...]<br>
> >>>>><br>
> >>>>> [4802/5201] Linking CXX executable bin/lld<br>
> >>>>> FAILED: bin/lld<br>
> >>>>> : && /home/usr4/c74014i/opt/clang/current/bin/clang++ -stdlib=libc++<br>
> >>>>> -fPIC -fvisibility-inlines-hidden -Werror=date-time<br>
> >>>>> -Werror=unguarded-availability-new -Wall -Wextra -Wno-unused-parameter<br>
> >>>>> -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -pedantic<br>
> >>>>> -Wno-long-long -Wimplicit-fallthrough -Wcovered-switch-default<br>
> >>>>> -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor<br>
> >>>>> -Wstring-conversion -fdiagnostics-color -ffunction-sections -fdata-sections<br>
> >>>>> -O3 -DNDEBUG -stdlib=libc++ -fuse-ld=lld -Wl,--color-diagnostics<br>
> >>>>> -Wl,-allow-shlib-undefined -Wl,--export-dynamic -Wl,-O3<br>
> >>>>> tools/lld/tools/lld/CMakeFiles/lld.dir/lld.cpp.o -o bin/lld<br>
> >>>>> -Wl,-rpath,"\$ORIGIN/../lib" lib/libLLVMSupport.a -lpthread<br>
> >>>>> lib/liblldCommon.a lib/liblldCOFF.a lib/liblldDriver.a lib/liblldELF.a<br>
> >>>>> lib/liblldMinGW.a lib/liblldWasm.a lib/liblldMachO.a<br>
> >>>>> lib/liblldReaderWriter.a lib/liblldYAML.a lib/liblldCore.a<br>
> >>>>> lib/liblldCOFF.a lib/libLLVMDebugInfoPDB.a lib/libLLVMLibDriver.a<br>
> >>>>> lib/libLLVMWindowsManifest.a /usr/lib64/libxml2.so lib/liblldCommon.a<br>
> >>>>> lib/libLLVMOption.a lib/libLLVMAArch64CodeGen.a<br>
> >>>>> lib/libLLVMAArch64AsmParser.a lib/libLLVMAArch64Disassembler.a<br>
> >>>>> lib/libLLVMAArch64Desc.a lib/libLLVMAArch64Info.a<br>
> >>>>> lib/libLLVMAArch64Utils.a lib/libLLVMAMDGPUCodeGen.a<br>
> >>>>> lib/libLLVMMIRParser.a lib/libLLVMAMDGPUAsmParser.a<br>
> >>>>> lib/libLLVMAMDGPUDisassembler.a lib/libLLVMAMDGPUDesc.a<br>
> >>>>> lib/libLLVMAMDGPUInfo.a lib/libLLVMAMDGPUUtils.a lib/libLLVMARMCodeGen.a<br>
> >>>>> lib/libLLVMARMAsmParser.a lib/libLLVMARMDisassembler.a<br>
> >>>>> lib/libLLVMARMDesc.a lib/libLLVMARMInfo.a lib/libLLVMARMUtils.a<br>
> >>>>> lib/libLLVMAVRCodeGen.a lib/libLLVMAVRAsmParser.a lib/libLLVMAVRDesc.a<br>
> >>>>> lib/libLLVMAVRDisassembler.a lib/libLLVMAVRInfo.a<br>
> >>>>> lib/libLLVMBPFCodeGen.a lib/libLLVMBPFAsmParser.a lib/libLLVMBPFDesc.a<br>
> >>>>> lib/libLLVMBPFDisassembler.a lib/libLLVMBPFInfo.a<br>
> >>>>> lib/libLLVMHexagonCodeGen.a lib/libLLVMHexagonAsmParser.a<br>
> >>>>> lib/libLLVMHexagonDisassembler.a lib/libLLVMHexagonDesc.a<br>
> >>>>> lib/libLLVMHexagonInfo.a lib/libLLVMLanaiCodeGen.a<br>
> >>>>> lib/libLLVMLanaiAsmParser.a lib/libLLVMLanaiDisassembler.a<br>
> >>>>> lib/libLLVMLanaiDesc.a lib/libLLVMLanaiInfo.a lib/libLLVMMipsCodeGen.a<br>
> >>>>> lib/libLLVMMipsAsmParser.a lib/libLLVMMipsDesc.a<br>
> >>>>> lib/libLLVMMipsDisassembler.a lib/libLLVMMipsInfo.a<br>
> >>>>> lib/libLLVMMSP430CodeGen.a lib/libLLVMMSP430AsmParser.a<br>
> >>>>> lib/libLLVMMSP430Desc.a lib/libLLVMMSP430Disassembler.a<br>
> >>>>> lib/libLLVMMSP430Info.a lib/libLLVMNVPTXCodeGen.a lib/libLLVMNVPTXDesc.a<br>
> >>>>> lib/libLLVMNVPTXInfo.a lib/libLLVMPowerPCCodeGen.a<br>
> >>>>> lib/libLLVMPowerPCAsmParser.a lib/libLLVMPowerPCDesc.a<br>
> >>>>> lib/libLLVMPowerPCDisassembler.a lib/libLLVMPowerPCInfo.a<br>
> >>>>> lib/libLLVMRISCVCodeGen.a lib/libLLVMRISCVAsmParser.a<br>
> >>>>> lib/libLLVMRISCVDesc.a lib/libLLVMRISCVDisassembler.a<br>
> >>>>> lib/libLLVMRISCVInfo.a lib/libLLVMRISCVUtils.a lib/libLLVMSparcCodeGen.a<br>
> >>>>> lib/libLLVMSparcAsmParser.a lib/libLLVMSparcDesc.a<br>
> >>>>> lib/libLLVMSparcDisassembler.a lib/libLLVMSparcInfo.a<br>
> >>>>> lib/libLLVMSystemZCodeGen.a lib/libLLVMSystemZAsmParser.a<br>
> >>>>> lib/libLLVMSystemZDisassembler.a lib/libLLVMSystemZDesc.a<br>
> >>>>> lib/libLLVMSystemZInfo.a lib/libLLVMWebAssemblyCodeGen.a<br>
> >>>>> lib/libLLVMWebAssemblyAsmParser.a lib/libLLVMWebAssemblyDisassembler.a<br>
> >>>>> lib/libLLVMWebAssemblyDesc.a lib/libLLVMWebAssemblyInfo.a<br>
> >>>>> lib/libLLVMX86CodeGen.a lib/libLLVMCFGuard.a lib/libLLVMGlobalISel.a<br>
> >>>>> lib/libLLVMX86AsmParser.a lib/libLLVMX86Desc.a<br>
> >>>>> lib/libLLVMX86Disassembler.a lib/libLLVMX86Info.a lib/libLLVMX86Utils.a<br>
> >>>>> lib/libLLVMXCoreCodeGen.a lib/libLLVMAsmPrinter.a<br>
> >>>>> lib/libLLVMDebugInfoDWARF.a lib/libLLVMSelectionDAG.a<br>
> >>>>> lib/libLLVMXCoreDesc.a lib/libLLVMXCoreDisassembler.a<br>
> >>>>> lib/libLLVMMCDisassembler.a lib/libLLVMXCoreInfo.a lib/libLLVMLTO.a<br>
> >>>>> lib/libLLVMObjCARCOpts.a lib/libLLVMPasses.a lib/libLLVMCodeGen.a<br>
> >>>>> lib/libLLVMTarget.a lib/libLLVMCoroutines.a lib/libLLVMipo.a<br>
> >>>>> lib/libLLVMBitWriter.a lib/libLLVMScalarOpts.a lib/libLLVMVectorize.a<br>
> >>>>> lib/libLLVMAggressiveInstCombine.a lib/libLLVMInstCombine.a<br>
> >>>>> lib/libLLVMLinker.a lib/libLLVMFrontendOpenMP.a lib/libLLVMIRReader.a<br>
> >>>>> lib/libLLVMAsmParser.a lib/libLLVMInstrumentation.a<br>
> >>>>> lib/libLLVMTransformUtils.a lib/libLLVMAnalysis.a lib/libLLVMObject.a<br>
> >>>>> lib/libLLVMBitReader.a lib/libLLVMMCParser.a lib/libLLVMMC.a<br>
> >>>>> lib/libLLVMDebugInfoCodeView.a lib/libLLVMDebugInfoMSF.a<br>
> >>>>> lib/libLLVMTextAPI.a lib/libLLVMProfileData.a lib/libLLVMCore.a<br>
> >>>>> lib/libLLVMBinaryFormat.a lib/libLLVMRemarks.a<br>
> >>>>> lib/libLLVMBitstreamReader.a lib/libLLVMSupport.a -lz -lrt -ldl<br>
> >>>>> -ltinfo -lpthread -lm lib/libLLVMDemangle.a && cd<br>
> >>>>> /tmp/build/202003290405/tools/lld/tools/lld &&<br>
> >>>>> /home/usr4/c74014i/opt/cmake-3.16.3-Linux-x86_64/bin/cmake -E<br>
> >>>>> create_symlink lld /tmp/build/202003290405/./bin/lld-link && cd<br>
> >>>>> /tmp/build/202003290405/tools/lld/tools/lld &&<br>
> >>>>> /home/usr4/c74014i/opt/cmake-3.16.3-Linux-x86_64/bin/cmake -E<br>
> >>>>> create_symlink lld /tmp/build/202003290405/./bin/ld.lld && cd<br>
> >>>>> /tmp/build/202003290405/tools/lld/tools/lld &&<br>
> >>>>> /home/usr4/c74014i/opt/cmake-3.16.3-Linux-x86_64/bin/cmake -E<br>
> >>>>> create_symlink lld /tmp/build/202003290405/./bin/ld64.lld && cd<br>
> >>>>> /tmp/build/202003290405/tools/lld/tools/lld &&<br>
> >>>>> /home/usr4/c74014i/opt/cmake-3.16.3-Linux-x86_64/bin/cmake -E<br>
> >>>>> create_symlink lld /tmp/build/202003290405/./bin/wasm-ld<br>
> >>>>> terminating with uncaught exception of type std::__1::system_error:<br>
> >>>>> thread constructor failed: Resource temporarily unavailable<br>
> >>>>> PLEASE submit a bug report to <a href="https://bugs.llvm.org/" rel="noreferrer" target="_blank">https://bugs.llvm.org/</a> and include the<br>
> >>>>> crash backtrace.<br>
> >>>>> #0 0x00000000007924f4 PrintStackTraceSignalHandler(void*)<br>
> >>>>> (/home/usr4/c74014i/opt/clang/current/bin/ld.lld+0x7924f4)<br>
> >>>>> #1 0x00000000007902ce llvm::sys::RunSignalHandlers()<br>
> >>>>> (/home/usr4/c74014i/opt/clang/current/bin/ld.lld+0x7902ce)<br>
> >>>>> #2 0x0000000000792bd5 SignalHandler(int)<br>
> >>>>> (/home/usr4/c74014i/opt/clang/current/bin/ld.lld+0x792bd5)<br>
> >>>>> #3 0x00007fddd54bb630 __restore_rt (/lib64/libpthread.so.0+0xf630)<br>
> >>>>> #4 0x00007fddd3b40377 raise<br>
> >>>>> /usr/src/debug/glibc-2.17-c758a686/signal/../nptl/sysdeps/unix/sysv/linux/raise.c:55:0<br>
> >>>>> #5 0x00007fddd3b41a68 abort<br>
> >>>>> /usr/src/debug/glibc-2.17-c758a686/stdlib/abort.c:92:0<br>
> >>>>> #6 0x00007fddd411ae8b<br>
> >>>>> (/home/usr4/c74014i/opt/clang/202003290200/bin/../lib/libc++abi.so.1+0x2be8b)<br>
> >>>>> #7 0x00007fddd40fdb9f demangling_terminate_handler()<br>
> >>>>> (/home/usr4/c74014i/opt/clang/202003290200/bin/../lib/libc++abi.so.1+0xeb9f)<br>
> >>>>> #8 0x00007fddd411a0a3 std::__terminate(void (*)())<br>
> >>>>> (/home/usr4/c74014i/opt/clang/202003290200/bin/../lib/libc++abi.so.1+0x2b0a3)<br>
> >>>>> #9 0x00007fddd411ce06<br>
> >>>>> (/home/usr4/c74014i/opt/clang/202003290200/bin/../lib/libc++abi.so.1+0x2de06)<br>
> >>>>> #10 0x00007fddd411cd9f<br>
> >>>>> (/home/usr4/c74014i/opt/clang/202003290200/bin/../lib/libc++abi.so.1+0x2dd9f)<br>
> >>>>> #11 0x00007fddd43bded4 std::__1::__throw_system_error(int, char const*)<br>
> >>>>> (/home/usr4/c74014i/opt/clang/202003290200/bin/../lib/libc++.so.1+0x90ed4)<br>
> >>>>> #12 0x0000000002a7a316 void*<br>
> >>>>> std::__1::__thread_proxy<std::__1::tuple<std::__1::unique_ptr<std::__1::__thread_struct,<br>
> >>>>> std::__1::default_delete<std::__1::__thread_struct> >,<br>
> >>>>> llvm::parallel::detail::(anonymous<br>
> >>>>> namespace)::ThreadPoolExecutor::ThreadPoolExecutor(llvm::ThreadPoolStrategy)::'lambda'()><br>
> >>>>> >(void*) (/home/usr4/c74014i/opt/clang/current/bin/ld.lld+0x2a7a316)<br>
> >>>>> #13 0x00007fddd54b3ea5 start_thread<br>
> >>>>> /usr/src/debug/glibc-2.17-c758a686/nptl/pthread_create.c:307:0<br>
> >>>>> #14 0x00007fddd3c088cd clone<br>
> >>>>> /usr/src/debug////////glibc-2.17-c758a686/misc/../sysdeps/unix/sysv/linux/x86_64/clone.S:113:0<br>
> >>>>> clang-11: error: unable to execute command: Aborted<br>
> >>>>> clang-11: error: linker command failed due to signal (use -v to see<br>
> >>>>> invocation)<br>
> >>>>><br>
> >>>>><br>
> >>>>><br>
> >>>>> On Sun, Mar 29, 2020 at 1:44 AM Nemanja Ivanovic <<br>
> >>>>> <a href="mailto:nemanja.i.ibm@gmail.com" target="_blank">nemanja.i.ibm@gmail.com</a> <mailto:<a href="mailto:nemanja.i.ibm@gmail.com" target="_blank">nemanja.i.ibm@gmail.com</a>>> wrote:<br>
> >>>>><br>
> >>>>> The discussion in <a href="https://reviews.llvm.org/D76240" rel="noreferrer" target="_blank">https://reviews.llvm.org/D76240</a><br>
> >>>>><br>
> >>>>> may be of interest to the participants of this thread. Specifically,<br>
> >>>>> Fangrui's planned work on a command line option to limit threads for LLD.<br>
> >>>>> Until that becomes a reality, you might want to use the CMake variable<br>
> >>>>> -DLLVM_ENABLE_THREADS=OFF when building the LLD that you are using to<br>
> >>>>> prevent parallelism.<br>
> >>>>><br>
> >>>>><br>
> >>>>><br>
> >>>>> On Sat, Mar 28, 2020 at 12:32 PM Alexandre Ganea via llvm-dev <<br>
> >>>>> <a href="mailto:llvm-dev@lists.llvm.org" target="_blank">llvm-dev@lists.llvm.org</a> <mailto:<a href="mailto:llvm-dev@lists.llvm.org" target="_blank">llvm-dev@lists.llvm.org</a>>> wrote:<br>
> >>>>><br>
> >>>>> Alex :<br>
> >>>>><br>
> >>>>> Can you please try `numactl` or `taskset` after<br>
> >>>>> <a href="https://github.com/llvm/llvm-project/commit/09158252f777c2e2f06a86b154c44abcbcf9bb74" rel="noreferrer" target="_blank">https://github.com/llvm/llvm-project/commit/09158252f777c2e2f06a86b154c44abcbcf9bb74</a><br>
> >>>>> ?<br>
> >>>>><br>
> >>>>><br>
> >>>>><br>
> >>>>> There was a tiny bug in how *sched_getaffinity*() was used, see:<br>
> >>>>> <a href="https://reviews.llvm.org/D75153#1942336" rel="noreferrer" target="_blank">https://reviews.llvm.org/D75153#1942336</a><br>
> >>>>><br>
> >>>>><br>
> >>>>><br>
> >>>>> *De :* Alex Brachet-Mialot <<a href="mailto:alexbrachetmialot@gmail.com" target="_blank">alexbrachetmialot@gmail.com</a> <mailto:<a href="mailto:alexbrachetmialot@gmail.com" target="_blank">alexbrachetmialot@gmail.com</a>>><br>
> >>>>> *Envoyé :* March 28, 2020 12:11 PM<br>
> >>>>> *À :* Itaru Kitayama <<a href="mailto:itaru.kitayama@gmail.com" target="_blank">itaru.kitayama@gmail.com</a> <mailto:<a href="mailto:itaru.kitayama@gmail.com" target="_blank">itaru.kitayama@gmail.com</a>>><br>
> >>>>> *Cc :* LLVM Dev <<a href="mailto:llvm-dev@lists.llvm.org" target="_blank">llvm-dev@lists.llvm.org</a> <mailto:<a href="mailto:llvm-dev@lists.llvm.org" target="_blank">llvm-dev@lists.llvm.org</a>>>; Alexandre Ganea <<br>
> >>>>> <a href="mailto:alexandre.ganea@ubisoft.com" target="_blank">alexandre.ganea@ubisoft.com</a> <mailto:<a href="mailto:alexandre.ganea@ubisoft.com" target="_blank">alexandre.ganea@ubisoft.com</a>>>; Fāng-ruì Sòng <<a href="mailto:maskray@google.com" target="_blank">maskray@google.com</a> <mailto:<a href="mailto:maskray@google.com" target="_blank">maskray@google.com</a>>><br>
> >>>>> *Objet :* Re: [llvm-dev] LLD issue on a massively parallel build<br>
> >>>>> machine<br>
> >>>>><br>
> >>>>><br>
> >>>>><br>
> >>>>> I also run into problems with lld on machines with lots of cores (208),<br>
> >>>>> but I run into rlimits for number of processes I can create, something<br>
> >>>>> outside of my control.<br>
> >>>>><br>
> >>>>><br>
> >>>>><br>
> >>>>> Unfortunately things like numactl or taskset do not limit the<br>
> >>>>> concurrency of lld currently.<br>
> >>>>><br>
> >>>>><br>
> >>>>><br>
> >>>>> On Sat, Mar 28, 2020 at 4:10 AM Itaru Kitayama via llvm-dev <<br>
> >>>>> <a href="mailto:llvm-dev@lists.llvm.org" target="_blank">llvm-dev@lists.llvm.org</a> <mailto:<a href="mailto:llvm-dev@lists.llvm.org" target="_blank">llvm-dev@lists.llvm.org</a>>> wrote:<br>
> >>>>><br>
> >>>>> Hi,<br>
> >>>>><br>
> >>>>> On a 1296-core Intel machine with 376 GB, setting<br>
> >>>>><br>
> >>>>><br>
> >>>>><br>
> >>>>> -DLLVM_PARALLEL_LINK_JOB=1<br>
> >>>>><br>
> >>>>><br>
> >>>>><br>
> >>>>> does not help (switching back to ld scales) see:<br>
> >>>>><br>
> >>>>><br>
> >>>>><br>
> >>>>> [5085/5201] Linking CXX executable bin/clang-11<br>
> >>>>> FAILED: bin/clang-11<br>
> >>>>> : && /home/usr4/c74014i/opt/clang/current/bin/clang++ -stdlib=libc++<br>
> >>>>> -fPIC -fvisibility-inlines-hidden -Werror=date-time<br>
> >>>>> -Werror=unguarded-availability-new -Wall -Wextra -Wno-unused-parameter<br>
> >>>>> -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -pedantic<br>
> >>>>> -Wno-long-long -Wimplicit-fallthrough -Wcovered-switch-default<br>
> >>>>> -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor<br>
> >>>>> -Wstring-conversion -fdiagnostics-color -ffunction-sections -fdata-sections<br>
> >>>>> -fno-common -Woverloaded-virtual -Wno-nested-anon-types -O3 -DNDEBUG<br>
> >>>>> -stdlib=libc++ -fuse-ld=lld -Wl,--color-diagnostics<br>
> >>>>> -Wl,-allow-shlib-undefined -Wl,--export-dynamic -Wl,-O3<br>
> >>>>> tools/clang/tools/driver/CMakeFiles/clang.dir/driver.cpp.o<br>
> >>>>> tools/clang/tools/driver/CMakeFiles/clang.dir/cc1_main.cpp.o<br>
> >>>>> tools/clang/tools/driver/CMakeFiles/clang.dir/cc1as_main.cpp.o<br>
> >>>>> tools/clang/tools/driver/CMakeFiles/clang.dir/cc1gen_reproducer_main.cpp.o<br>
> >>>>> -o bin/clang-11 -Wl,-rpath,"\$ORIGIN/../lib" lib/libLLVMAArch64CodeGen.a<br>
> >>>>> lib/libLLVMAArch64AsmParser.a lib/libLLVMAArch64Desc.a<br>
> >>>>> lib/libLLVMAArch64Disassembler.a lib/libLLVMAArch64Info.a<br>
> >>>>> lib/libLLVMAArch64Utils.a lib/libLLVMAMDGPUCodeGen.a<br>
> >>>>> lib/libLLVMAMDGPUAsmParser.a lib/libLLVMAMDGPUDesc.a<br>
> >>>>> lib/libLLVMAMDGPUDisassembler.a lib/libLLVMAMDGPUInfo.a<br>
> >>>>> lib/libLLVMAMDGPUUtils.a lib/libLLVMARMCodeGen.a<br>
> >>>>> lib/libLLVMARMAsmParser.a lib/libLLVMARMDesc.a<br>
> >>>>> lib/libLLVMARMDisassembler.a lib/libLLVMARMInfo.a lib/libLLVMARMUtils.a<br>
> >>>>> lib/libLLVMAVRCodeGen.a lib/libLLVMAVRAsmParser.a lib/libLLVMAVRDesc.a<br>
> >>>>> lib/libLLVMAVRDisassembler.a lib/libLLVMAVRInfo.a<br>
> >>>>> lib/libLLVMBPFCodeGen.a lib/libLLVMBPFAsmParser.a lib/libLLVMBPFDesc.a<br>
> >>>>> lib/libLLVMBPFDisassembler.a lib/libLLVMBPFInfo.a<br>
> >>>>> lib/libLLVMHexagonCodeGen.a lib/libLLVMHexagonAsmParser.a<br>
> >>>>> lib/libLLVMHexagonDesc.a lib/libLLVMHexagonDisassembler.a<br>
> >>>>> lib/libLLVMHexagonInfo.a lib/libLLVMLanaiCodeGen.a<br>
> >>>>> lib/libLLVMLanaiAsmParser.a lib/libLLVMLanaiDesc.a<br>
> >>>>> lib/libLLVMLanaiDisassembler.a lib/libLLVMLanaiInfo.a<br>
> >>>>> lib/libLLVMMipsCodeGen.a lib/libLLVMMipsAsmParser.a<br>
> >>>>> lib/libLLVMMipsDesc.a lib/libLLVMMipsDisassembler.a<br>
> >>>>> lib/libLLVMMipsInfo.a lib/libLLVMMSP430CodeGen.a<br>
> >>>>> lib/libLLVMMSP430AsmParser.a lib/libLLVMMSP430Desc.a<br>
> >>>>> lib/libLLVMMSP430Disassembler.a lib/libLLVMMSP430Info.a<br>
> >>>>> lib/libLLVMNVPTXCodeGen.a lib/libLLVMNVPTXDesc.a lib/libLLVMNVPTXInfo.a<br>
> >>>>> lib/libLLVMPowerPCCodeGen.a lib/libLLVMPowerPCAsmParser.a<br>
> >>>>> lib/libLLVMPowerPCDesc.a lib/libLLVMPowerPCDisassembler.a<br>
> >>>>> lib/libLLVMPowerPCInfo.a lib/libLLVMRISCVCodeGen.a<br>
> >>>>> lib/libLLVMRISCVAsmParser.a lib/libLLVMRISCVDesc.a<br>
> >>>>> lib/libLLVMRISCVDisassembler.a lib/libLLVMRISCVInfo.a<br>
> >>>>> lib/libLLVMRISCVUtils.a lib/libLLVMSparcCodeGen.a<br>
> >>>>> lib/libLLVMSparcAsmParser.a lib/libLLVMSparcDesc.a<br>
> >>>>> lib/libLLVMSparcDisassembler.a lib/libLLVMSparcInfo.a<br>
> >>>>> lib/libLLVMSystemZCodeGen.a lib/libLLVMSystemZAsmParser.a<br>
> >>>>> lib/libLLVMSystemZDesc.a lib/libLLVMSystemZDisassembler.a<br>
> >>>>> lib/libLLVMSystemZInfo.a lib/libLLVMWebAssemblyCodeGen.a<br>
> >>>>> lib/libLLVMWebAssemblyAsmParser.a lib/libLLVMWebAssemblyDesc.a<br>
> >>>>> lib/libLLVMWebAssemblyDisassembler.a lib/libLLVMWebAssemblyInfo.a<br>
> >>>>> lib/libLLVMX86CodeGen.a lib/libLLVMX86AsmParser.a lib/libLLVMX86Desc.a<br>
> >>>>> lib/libLLVMX86Disassembler.a lib/libLLVMX86Info.a lib/libLLVMX86Utils.a<br>
> >>>>> lib/libLLVMXCoreCodeGen.a lib/libLLVMXCoreDesc.a<br>
> >>>>> lib/libLLVMXCoreDisassembler.a lib/libLLVMXCoreInfo.a<br>
> >>>>> lib/libLLVMAnalysis.a lib/libLLVMCodeGen.a lib/libLLVMCore.a<br>
> >>>>> lib/libLLVMipo.a lib/libLLVMAggressiveInstCombine.a<br>
> >>>>> lib/libLLVMInstCombine.a lib/libLLVMInstrumentation.a lib/libLLVMMC.a<br>
> >>>>> lib/libLLVMMCParser.a lib/libLLVMObjCARCOpts.a lib/libLLVMOption.a<br>
> >>>>> lib/libLLVMScalarOpts.a lib/libLLVMSupport.a lib/libLLVMTransformUtils.a<br>
> >>>>> lib/libLLVMVectorize.a -lpthread lib/libclangBasic.a<br>
> >>>>> lib/libclangCodeGen.a lib/libclangDriver.a lib/libclangFrontend.a<br>
> >>>>> lib/libclangFrontendTool.a lib/libclangSerialization.a<br>
> >>>>> lib/libLLVMAArch64Desc.a lib/libLLVMAArch64Info.a<br>
> >>>>> lib/libLLVMAArch64Utils.a lib/libLLVMMIRParser.a lib/libLLVMAMDGPUDesc.a<br>
> >>>>> lib/libLLVMAMDGPUInfo.a lib/libLLVMAMDGPUUtils.a lib/libLLVMARMDesc.a<br>
> >>>>> lib/libLLVMARMInfo.a lib/libLLVMARMUtils.a lib/libLLVMHexagonDesc.a<br>
> >>>>> lib/libLLVMHexagonInfo.a lib/libLLVMLanaiDesc.a lib/libLLVMLanaiInfo.a<br>
> >>>>> lib/libLLVMSystemZDesc.a lib/libLLVMSystemZInfo.a<br>
> >>>>> lib/libLLVMWebAssemblyDesc.a lib/libLLVMWebAssemblyInfo.a<br>
> >>>>> lib/libLLVMCFGuard.a lib/libLLVMGlobalISel.a lib/libLLVMAsmPrinter.a<br>
> >>>>> lib/libLLVMDebugInfoDWARF.a lib/libLLVMSelectionDAG.a<br>
> >>>>> lib/libLLVMMCDisassembler.a lib/libclangCodeGen.a lib/libLLVMCoverage.a<br>
> >>>>> lib/libLLVMLTO.a lib/libLLVMObjCARCOpts.a lib/libLLVMPasses.a<br>
> >>>>> lib/libLLVMCodeGen.a lib/libLLVMTarget.a lib/libLLVMCoroutines.a<br>
> >>>>> lib/libLLVMipo.a lib/libLLVMInstrumentation.a lib/libLLVMVectorize.a<br>
> >>>>> lib/libLLVMBitWriter.a lib/libLLVMIRReader.a lib/libLLVMAsmParser.a<br>
> >>>>> lib/libLLVMLinker.a lib/libLLVMScalarOpts.a<br>
> >>>>> lib/libLLVMAggressiveInstCombine.a lib/libLLVMInstCombine.a<br>
> >>>>> lib/libclangRewriteFrontend.a lib/libclangARCMigrate.a<br>
> >>>>> lib/libclangStaticAnalyzerFrontend.a lib/libclangStaticAnalyzerCheckers.a<br>
> >>>>> lib/libclangStaticAnalyzerCore.a lib/libclangCrossTU.a<br>
> >>>>> lib/libclangIndex.a lib/libclangFrontend.a lib/libclangDriver.a<br>
> >>>>> lib/libLLVMOption.a lib/libclangParse.a lib/libclangSerialization.a<br>
> >>>>> lib/libclangSema.a lib/libclangAnalysis.a lib/libclangASTMatchers.a<br>
> >>>>> lib/libclangEdit.a lib/libclangFormat.a lib/libclangToolingInclusions.a<br>
> >>>>> lib/libclangToolingCore.a lib/libclangAST.a lib/libLLVMFrontendOpenMP.a<br>
> >>>>> lib/libLLVMTransformUtils.a lib/libLLVMAnalysis.a<br>
> >>>>> lib/libLLVMProfileData.a lib/libLLVMObject.a lib/libLLVMMCParser.a<br>
> >>>>> lib/libLLVMBitReader.a lib/libLLVMTextAPI.a lib/libclangRewrite.a<br>
> >>>>> lib/libclangLex.a lib/libclangBasic.a lib/libLLVMCore.a<br>
> >>>>> lib/libLLVMRemarks.a lib/libLLVMBitstreamReader.a lib/libLLVMMC.a<br>
> >>>>> lib/libLLVMBinaryFormat.a lib/libLLVMDebugInfoCodeView.a<br>
> >>>>> lib/libLLVMDebugInfoMSF.a lib/libLLVMSupport.a -lz -lrt -ldl -ltinfo<br>
> >>>>> -lpthread -lm lib/libLLVMDemangle.a && :<br>
> >>>>> ld.lld: error: failed to open bin/clang-11: Cannot allocate memory<br>
> >>>>><br>
> >>>>> _______________________________________________<br>
> >>>>> LLVM Developers mailing list<br>
> >>>>> <a href="mailto:llvm-dev@lists.llvm.org" target="_blank">llvm-dev@lists.llvm.org</a> <mailto:<a href="mailto:llvm-dev@lists.llvm.org" target="_blank">llvm-dev@lists.llvm.org</a>><br>
> >>>>> <a href="https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev" rel="noreferrer" target="_blank">https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev</a><br>
> >>>>><br>
> >>>>> _______________________________________________<br>
> >>>>> LLVM Developers mailing list<br>
> >>>>> <a href="mailto:llvm-dev@lists.llvm.org" target="_blank">llvm-dev@lists.llvm.org</a> <mailto:<a href="mailto:llvm-dev@lists.llvm.org" target="_blank">llvm-dev@lists.llvm.org</a>><br>
> >>>>> <a href="https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev" rel="noreferrer" target="_blank">https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev</a><br>
> >>>>><br>
> >>>>><br>
> <br>
> >_______________________________________________<br>
> >LLVM Developers mailing list<br>
> ><a href="mailto:llvm-dev@lists.llvm.org" target="_blank">llvm-dev@lists.llvm.org</a> <mailto:<a href="mailto:llvm-dev@lists.llvm.org" target="_blank">llvm-dev@lists.llvm.org</a>><br>
> ><a href="https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev" rel="noreferrer" target="_blank">https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev</a><br>
> <br>
> <br>
> <br>
> _______________________________________________<br>
> LLVM Developers mailing list<br>
> <a href="mailto:llvm-dev@lists.llvm.org" target="_blank">llvm-dev@lists.llvm.org</a><br>
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> <br>
<br>
</blockquote></div></div>