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Received: from 91-160-117-201.subs.proxad.net ([91.160.117.201]:59284 helo=ribbon) by fencepost.gnu.org with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nqWn2-0007Oc-Fe; Mon, 16 May 2022 05:13:20 -0400 From: Ludovic =?UTF-8?Q?Court=C3=A8s?= References: <87fslcaznn.fsf@gmail.com> <87mtfj174l.fsf@gnu.org> <878rr2kug6.fsf_-_@gmail.com> <87pmke6ig4.fsf@gnu.org> Date: Mon, 16 May 2022 11:13:17 +0200 In-Reply-To: <87pmke6ig4.fsf@gnu.org> (Mathieu Othacehe's message of "Mon, 16 May 2022 09:32:43 +0200") Message-ID: <87o7zxalhu.fsf@gnu.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list X-BeenThere: bug-guix@gnu.org List-Id: Bug reports for GNU Guix List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: bug-guix-bounces+larch=yhetil.org@gnu.org Sender: "bug-Guix" X-Migadu-Flow: FLOW_IN X-Migadu-To: larch@yhetil.org X-Migadu-Country: US ARC-Message-Signature: i=1; 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aspmx1.migadu.com; dkim=fail ("headers rsa verify failed") header.d=gnu.org header.s=fencepost-gnu-org header.b=IVuQC03w; dmarc=pass (policy=none) header.from=gnu.org; spf=pass (aspmx1.migadu.com: domain of "bug-guix-bounces+larch=yhetil.org@gnu.org" designates 209.51.188.17 as permitted sender) smtp.mailfrom="bug-guix-bounces+larch=yhetil.org@gnu.org" X-Migadu-Spam-Score: -5.33 Authentication-Results: aspmx1.migadu.com; dkim=fail ("headers rsa verify failed") header.d=gnu.org header.s=fencepost-gnu-org header.b=IVuQC03w; dmarc=pass (policy=none) header.from=gnu.org; spf=pass (aspmx1.migadu.com: domain of "bug-guix-bounces+larch=yhetil.org@gnu.org" designates 209.51.188.17 as permitted sender) smtp.mailfrom="bug-guix-bounces+larch=yhetil.org@gnu.org" X-Migadu-Queue-Id: 1E4B31A06F X-Spam-Score: -5.33 X-Migadu-Scanner: scn0.migadu.com X-TUID: xbZK34KtIqLu Hi! Mathieu Othacehe skribis: > I noticed this error: https://ci.guix.gnu.org/eval/320682/log/raw. > > The following lines can be caused by having a multi-threaded program: > (cuirass scripts evaluate) because of its par-for-each procedure, call > "primitive-fork" in open-bidirectional-pipe of (guix inferior). > > warning: call to primitive-fork while multiple threads are running; > further behavior unspecified. See "Processes" in the > manual, for more information. > > Not sure that it could cause the observed hang, Ludo what do you think? As you write, the warning comes from =E2=80=98open-bidirectional-pipe=E2=80= =99, added in commit bd86bbd300474204878e927f6cd3f0defa1662a5. I noticed it back then but as far as I could see, it was harmless (but definitely suboptimal): https://issues.guix.gnu.org/48007#11 Indeed, =E2=80=9Cmake cuirass-jobs=E2=80=9D works for me. I decided to go ahead and run =E2=80=98cuirass evaluate=E2=80=99 by hand to= gather more info: --8<---------------cut here---------------start------------->8--- ludo@berlin ~$ sudo su - cuirass -s /bin/sh -c "/gnu/store/qamrzl942khb7w0c= b4csyflnxfkwvvxq-cuirass-1.1.0-11.9f08035/bin/cuirass evaluate dbname=3Dcui= rass 323183" Computing Guix derivation for 'x86_64-linux'... | warning: call to primitive-fork while multiple threads are running; further behavior unspecified. See "Processes" in the manual, for more information. warning: call to primitive-fork while multiple threads are running; further behavior unspecified. See "Processes" in the manual, for more information. warning: call to primitive-fork while multiple threads are running; further behavior unspecified. See "Processes" in the manual, for more information. warning: call to primitive-fork while multiple threads are running; further behavior unspecified. See "Processes" in the manual, for more information. 2022-05-16T09:56:43 Registering builds for evaluation 323183. 2022-05-16T10:08:47 Registering builds for evaluation 323183. --8<---------------cut here---------------end--------------->8--- I straced it in another terminal. It did its work for a long while, and eventually activity stopped: --8<---------------cut here---------------start------------->8--- read(228, "nu/store/7gi4qsakz775z5wcmddg8xan7q806sj1-findutils-4.8.0\")) (#= :nix-name . \"findutils-4.8.0\") (#:sys"..., 4096) =3D 4096 read(228, "nrd-gcc-cross-x86_64-w64-mingw32-10.3.0.drv\" \"/gnu/store/ykrks= w421rd22zh4w3pc751r90wc881n-patch-2.7."..., 4096) =3D 4096 read(228, "wm-binutils-cross-x86_64-w64-mingw32-2.37.drv\" \"/gnu/store/xfh= 4965w2amrsl7x0h3dslrhndzn5bbz-linux-li"..., 4096) =3D 4096 read(228, "1ir-gawk-5.1.0.drv\" \"/gnu/store/p1d2w4fg1ljbyfs0ayv854snahcima= mk-libunistring-0.9.10.drv\" \"/gnu/stor"..., 4096) =3D 4096 read(228, "3ysc-guile-2.2.7.drv\" \"/gnu/store/b0ma6l61ad4dfb3030sl1ngvdlic= c523-glibc-utf8-locales-2.33.drv\" \"/gn"..., 4096) =3D 4096 read(228, "j6a5mc7w13xiw8136y4brv7w-xz-5.2.5.drv\" \"/gnu/store/w1bxsf02c4y= 0hj0nd39awv7i55ych641-libffi-3.3.drv\" "..., 4096) =3D 4096 read(228, "tore/qbqgamcpwgs2sw8lcr6pxl5y38fpyz0d-sed-4.8.drv\" \"/gnu/store= /qmsbxbgb758h6f7018snxlwn69w9w9i4-diff"..., 4096) =3D 4096 read(228, "oconf-2.69.drv\" \"/gnu/store/6n5mn2vkl4x4fab37sx1rmqyqxqcwd4y-l= ibidn2-2.3.1.drv\" \"/gnu/store/6q5cp0m2"..., 4096) =3D 4096 mmap(0x7fddd26af000, 65536, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS= , -1, 0) =3D 0x7fddd268f000 read(228, "-binutils-cross-x86_64-w64-mingw32-2.37.drv\" \"/gnu/store/wdmk9= llhdzx5y10mziss1i5z6q037a7z-guile-3.0."..., 4096) =3D 954 futex(0x7fdf015381f0, FUTEX_WAKE_PRIVATE, 1) =3D 1 futex(0x7fdf01546b00, FUTEX_WAIT_PRIVATE, 2, NULL) =3D -1 EAGAIN (Resource = temporarily unavailable) futex(0x7fdf015381f4, FUTEX_WAKE_PRIVATE, 1) =3D 1 futex(0x7fdf01546b00, FUTEX_WAKE_PRIVATE, 1) =3D 1 futex(0x7fdf01538f74, FUTEX_WAIT_BITSET_PRIVATE|FUTEX_CLOCK_REALTIME, 0, NU= LL, FUTEX_BITSET_MATCH_ANY) =3D ? ERESTARTSYS (To be restarted if SA_RESTAR= T is set) --- SIGPWR {si_signo=3DSIGPWR, si_code=3DSI_TKILL, si_pid=3D64599, si_uid= =3D997} --- rt_sigsuspend(~[INT QUIT ABRT BUS SEGV TERM XCPU RTMIN RT_1], 8) =3D ? ERES= TARTNOHAND (To be restarted if no handler) --- SIGXCPU {si_signo=3DSIGXCPU, si_code=3DSI_TKILL, si_pid=3D64599, si_uid= =3D997} --- rt_sigreturn({mask=3D~[INT QUIT ABRT BUS KILL SEGV TERM STOP RTMIN RT_1]}) = =3D -1 EINTR (Interrupted system call) rt_sigreturn({mask=3D[]}) =3D 202 futex(0x7fdf01538f74, FUTEX_WAIT_BITSET_PRIVATE|FUTEX_CLOCK_REALTIME, 0, NU= LL, FUTEX_BITSET_MATCH_ANY) =3D ? ERESTARTSYS (To be restarted if SA_RESTAR= T is set) --- SIGPWR {si_signo=3DSIGPWR, si_code=3DSI_TKILL, si_pid=3D64599, si_uid= =3D997} --- rt_sigsuspend(~[INT QUIT ABRT BUS SEGV TERM XCPU RTMIN RT_1], 8) =3D ? ERES= TARTNOHAND (To be restarted if no handler) --- SIGXCPU {si_signo=3DSIGXCPU, si_code=3DSI_TKILL, si_pid=3D64599, si_uid= =3D997} --- rt_sigreturn({mask=3D~[INT QUIT ABRT BUS KILL SEGV TERM STOP RTMIN RT_1]}) = =3D -1 EINTR (Interrupted system call) rt_sigreturn({mask=3D[]}) =3D 202 futex(0x7fdf01538f74, FUTEX_WAIT_BITSET_PRIVATE|FUTEX_CLOCK_REALTIME, 0, NU= LL, FUTEX_BITSET_MATCH_ANY) =3D ? ERESTARTSYS (To be restarted if SA_RESTAR= T is set) [=E2=80=A6] --- SIGXCPU {si_signo=3DSIGXCPU, si_code=3DSI_TKILL, si_pid=3D64599, si_uid= =3D997} --- rt_sigreturn({mask=3D~[INT QUIT ABRT BUS KILL SEGV TERM STOP RTMIN RT_1]}) = =3D -1 EINTR (Interrupted system call) rt_sigreturn({mask=3D[]}) =3D 202 futex(0x7fdf01538f74, FUTEX_WAIT_BITSET_PRIVATE|FUTEX_CLOCK_REALTIME, 0, NU= LL, FUTEX_BITSET_MATCH_ANY) =3D 0 futex(0x7fdf01546c00, FUTEX_WAKE_PRIVATE, 1) =3D 0 close(224) =3D 0 futex(0x7fdf01538f70, FUTEX_WAIT_BITSET_PRIVATE|FUTEX_CLOCK_REALTIME, 0, NU= LL, FUTEX_BITSET_MATCH_ANY [stops here] --8<---------------cut here---------------end--------------->8--- The =E2=80=98read=E2=80=99 calls are about getting the jobset alists; FD 22= 8 is a socket (to a =E2=80=98guix repl=E2=80=99 subprocess I presume). SIGPWR/SIGXCPU su= ggests attempts to make a stop-the-world GC. GDB shows that the process has 120 threads (it=E2=80=99s a 96-core machine,= but still=E2=80=A6) and most threads are stuck in pthread_cond_wait: --8<---------------cut here---------------start------------->8--- (gdb) bt #0 0x00007fdf01d62afa in __futex_abstimed_wait_common64 (futex_word=3Dfute= x_word@entry=3D0x7fded20cd8b4,=20 expected=3Dexpected@entry=3D0, clockid=3Dclockid@entry=3D0, abstime=3Da= bstime@entry=3D0x0, private=3Dprivate@entry=3D0,=20 cancel=3Dcancel@entry=3Dtrue) at ../sysdeps/nptl/futex-internal.c:74 #1 0x00007fdf01d62b5b in __GI___futex_abstimed_wait_cancelable64 (futex_wo= rd=3Dfutex_word@entry=3D0x7fded20cd8b4,=20 expected=3Dexpected@entry=3D0, clockid=3Dclockid@entry=3D0, abstime=3Da= bstime@entry=3D0x0, private=3Dprivate@entry=3D0) at ../sysdeps/nptl/futex-internal.c:123 #2 0x00007fdf01d5cab0 in __pthread_cond_wait_common (abstime=3D0x0, clocki= d=3D0, mutex=3D0x7fdef9c15fc0,=20 cond=3Dcond@entry=3D0x7fded20cd888) at pthread_cond_wait.c:504 #3 __pthread_cond_wait (cond=3Dcond@entry=3D0x7fded20cd888, mutex=3Dmutex@= entry=3D0x7fdef9c15fc0) at pthread_cond_wait.c:619 #4 0x00007fdf01ea2a55 in scm_pthread_cond_wait (cond=3Dcond@entry=3D0x7fde= d20cd888, mutex=3Dmutex@entry=3D0x7fdef9c15fc0) at threads.c:1605 #5 0x00007fdf01ea7b6b in block_self ( queue=3D((#) # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #= # # # # # # # # = # # # # # # # # #= # # # # # # # #<= smob thread 7fdedfa52e90> # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #), mutex=3Dmutex@entry=3D0x7fdef9c15fc0, waittime=3Dwa= ittime@entry=3D0x0) at threads.c:312 #6 0x00007fdf01eaa1cd in timed_wait (waittime=3D0x0, current_thread=3D0x7f= ded20cd6c0, c=3D0x7fdef9c10d20,=20 m=3D0x7fdef9c15fc0, kind=3DSCM_MUTEX_STANDARD) at threads.c:1331 #7 scm_timed_wait_condition_variable (cond=3D#,=20 mutex=3D#, timeout=3D#) at thre= ads.c:1424 #8 0x00007fded169a7f3 in ?? () #9 0x0000000000b83688 in ?? () #10 0x00007fded169a750 in ?? () #11 0x00007fdeec009e98 in ?? () #12 0x00007fdf01e57ccc in scm_jit_enter_mcode (thread=3D0x7fded20cd6c0, mco= de=3D0xb8369c "\034\330\003") at jit.c:6038 #13 0x00007fdf01eacf3c in vm_regular_engine (thread=3D0x7fded20cd6c0) at vm= -engine.c:360 #14 0x00007fdf01eba5e9 in scm_call_n (proc=3D, argv=3D, nargs=3D0) at vm.c:1608 #15 0x00007fdf01e1ea0e in scm_call_with_unblocked_asyncs (proc=3D#) at async.c:406 #16 0x00007fdf01ead336 in vm_regular_engine (thread=3D0x7fded20cd6c0) at vm= -engine.c:972 #17 0x00007fdf01eba5e9 in scm_call_n (proc=3D, argv=3D, nargs=3D0) at vm.c:1608 #18 0x00007fdf01ea9be6 in really_launch (d=3D0x7fdef730c860) at threads.c:7= 78 #19 0x00007fdf01e2085a in c_body (d=3D0x7fdec8c44d80) at continuations.c:430 #20 0x00007fded2874532 in ?? () #21 0x00007fdef9a227e0 in ?? () #22 0x00007fdef7d8c370 in ?? () #23 0x0000000000000048 in ?? () #24 0x00007fdf01e57ccc in scm_jit_enter_mcode (thread=3D0x7fded20cd6c0, mco= de=3D0xb81874 "\034<\003") at jit.c:6038 #25 0x00007fdf01eacf3c in vm_regular_engine (thread=3D0x7fded20cd6c0) at vm= -engine.c:360 #26 0x00007fdf01eba5e9 in scm_call_n (proc=3D, argv=3D, nargs=3D2) at vm.c:1608 #27 0x00007fdf01e2209a in scm_call_2 (proc=3D, arg1=3D, arg2=3D) at eval.c:503 #28 0x00007fdf01ed8752 in scm_c_with_exception_handler.constprop.0 (type=3D= #t,=20 handler_data=3Dhandler_data@entry=3D0x7fdec8c44d10, thunk_data=3Dthunk_= data@entry=3D0x7fdec8c44d10,=20 thunk=3D, handler=3D) at exceptions.c:170 #29 0x00007fdf01eaa88f in scm_c_catch (tag=3D, body=3D, body_data=3D,=20 handler=3D, handler_data=3D, pre_unwind_h= andler=3D,=20 pre_unwind_handler_data=3D0x7fdef9b97040) at throw.c:168 #30 0x00007fdf01e22e66 in scm_i_with_continuation_barrier (pre_unwind_handl= er=3D0x7fdf01e22b80 ,=20 pre_unwind_handler_data=3D0x7fdef9b97040, handler_data=3D0x7fdec8c44d80= , handler=3D0x7fdf01e298b0 ,=20 body_data=3D0x7fdec8c44d80, body=3D0x7fdf01e20850 ) at continua= tions.c:368 #31 scm_c_with_continuation_barrier (func=3D, data=3D) at continuations.c:464 #32 0x00007fdf01ea9b39 in with_guile (base=3D0x7fdec8c44e08, data=3D0x7fdec= 8c44e30) at threads.c:645 #33 0x00007fdf01d800ba in GC_call_with_stack_base () from /gnu/store/2lczkxbdbzh4gk7wh91bzrqrk7h5g1dl-libgc-8.0.4/lib/libgc.s= o.1 #34 0x00007fdf01ea216d in scm_i_with_guile (dynamic_state=3D= , data=3D0x7fdef730c860,=20 func=3D0x7fdf01ea9b70 ) at threads.c:688 #35 launch_thread (d=3D0x7fdef730c860) at threads.c:787 #36 0x00007fdf01d56d7e in start_thread (arg=3D0x7fdec8c45640) at pthread_cr= eate.c:473 #37 0x00007fdf01954eff in clone () at ../sysdeps/unix/sysv/linux/x86_64/clo= ne.S:95 --8<---------------cut here---------------end--------------->8--- There=E2=80=99s also one thread stuck in read(2): --8<---------------cut here---------------start------------->8--- (gdb) bt #0 __libc_read (nbytes=3D1, buf=3D0x7fdedf97bdd0, fd=3D7) at ../sysdeps/un= ix/sysv/linux/read.c:26 #1 __libc_read (fd=3D7, buf=3Dbuf@entry=3D0x7fdedf97bdd0, nbytes=3Dnbytes@= entry=3D1) at ../sysdeps/unix/sysv/linux/read.c:24 #2 0x00007fdf01e382e8 in fport_read (port=3D, dst=3D, start=3D, count=3D1) at fports.c:597 #3 0x00007fdf01e78d22 in scm_i_read_bytes (port=3Dport@entry=3D# 7fdef59b7180>,=20 dst=3D"#" =3D {...}, start=3Dstart@entry=3D0, count=3D1) at = ports.c:1566 #4 0x00007fdf01e7b1c7 in scm_fill_input (port=3Dport@entry=3D# 7fdef59b7180>,=20 minimum_size=3D1, minimum_size@entry=3D0, cur_out=3Dcur_out@entry=3D0x7= fde86fcc3e8,=20 avail_out=3Davail_out@entry=3D0x7fde86fcc3e0) at ports.c:2693 #5 0x00007fdf01e7b434 in peek_byte_or_eof (port=3Dport@entry=3D# 7fdef59b7180>,=20 buf_out=3Dbuf_out@entry=3D0x7fde86fcc448, cur_out=3Dcur_out@entry=3D0x7= fde86fcc440) at ports.c:1526 #6 0x00007fdf01e7c1b5 in maybe_consume_bom (port=3Dport@entry=3D# 7fdef59b7180>,=20 bom=3Dbom@entry=3D0x7fdf01ee56ad "\357\273\277scm_i_read= _bytes", bom_len=3Dbom_len@entry=3D3) at ports.c:2468 #7 0x00007fdf01e7b324 in port_clear_stream_start_for_bom_read (io_mode=3DB= OM_IO_TEXT,=20 port=3D# 7fdef59b7180>) at ports.c:= 2504 #8 scm_fill_input (port=3Dport@entry=3D# 7fdef59b7180>, minimum_size=3D1,=20 minimum_size@entry=3D0, cur_out=3Dcur_out@entry=3D0x7fde86fcc4e8, avail= _out=3Davail_out@entry=3D0x7fde86fcc4e0) at ports.c:2648 #9 0x00007fdf01e7b434 in peek_byte_or_eof (port=3Dport@entry=3D# 7fdef59b7180>,=20 buf_out=3Dbuf_out@entry=3D0x7fde86fcc548, cur_out=3Dcur_out@entry=3D0x7= fde86fcc540) at ports.c:1526 #10 0x00007fdf01e7b97c in peek_utf8_codepoint (port=3D# 7fdef59b7180>,=20 buf_out=3Dbuf_out@entry=3D0x7fde86fcc5a8, cur_out=3Dcur_out@entry=3D0x7= fde86fcc5a0, len_out=3Dlen_out@entry=3D0x7fde86fcc598) at ports.c:1790 #11 0x00007fdf01e7bee4 in peek_codepoint (len=3D0x7fde86fcc598, cur=3D0x7fd= e86fcc5a0, buf=3D0x7fde86fcc5a8,=20 port=3D) at ports.c:1984 #12 scm_peek_char (port=3D) at ports.c:2202 #13 0x00007fdef997b1ab in ?? () #14 0x0000000000b82ae0 in ?? () #15 0x00007fdef997b120 in ?? () #16 0x00007fdec4292c48 in ?? () #17 0x00007fdf01e57ccc in scm_jit_enter_mcode (thread=3D0x7fded1366000, mco= de=3D0xb82af0 "\034\234\003") at jit.c:6038 #18 0x00007fdf01eacf3c in vm_regular_engine (thread=3D0x7fded1366000) at vm= -engine.c:360 #19 0x00007fdf01eba5e9 in scm_call_n (proc=3D, argv=3D, nargs=3D0) at vm.c:1608 #20 0x00007fdf01e1ea0e in scm_call_with_unblocked_asyncs (proc=3D#) at async.c:406 --8<---------------cut here---------------end--------------->8--- A plausible scenario is a synchronization issue: =E2=80=98cuirass evaluate= =E2=80=99 got all the data it asked for from =E2=80=98guix repl=E2=80=99, but it=E2=80=99= s still waiting on read(2) even though there=E2=80=99s nothing left. (There are two child =E2= =80=98guix repl=E2=80=99 processes and both are waiting on read(0, =E2=80=A6).) Thoughts? Ludo=E2=80=99.