Hello, I tried running this: guix build --max-jobs=200 $(guix gc -R $(guix build -d inkscape --no-grafts) | sort) & \ guix build --max-jobs=200 $(guix gc -R $(guix build -d inkscape --no-grafts) | sort -r) … also in parallel with this (for good measure): guix build --max-jobs=200 $(guix gc -R $(guix build -d inkscape --no-grafts) | sort -R) Since we have 3 clients, that leads to 3 guix-daemon processes, and those are stuck in a deadlock: --8<---------------cut here---------------start------------->8--- $ ps aux | grep guix-daemon […] root 20501 0.6 0.0 39292 12012 ? Ss 15:51 0:01 guix-daemon 20455 root 20503 4.3 0.0 39420 12096 ? Ss 15:51 0:12 guix-daemon 20491 root 22154 0.0 0.0 39028 11016 ? Ss 15:52 0:00 guix-daemon 22148 $ sudo strace -p 22154 -t strace: Process 22154 attached 15:57:03 select(0, 0x7ffdca30b610, NULL, NULL, {tv_sec=1, tv_usec=314189}) = 0 (Timeout) 15:57:04 openat(AT_FDCWD, "/gnu/store/ghc9vcc8ydv305jz0spd73qrrf30gxik-binutils-bootstrap-0.lock", O_RDWR|O_CREAT, 0600) = 8 15:57:04 fcntl(8, F_GETFD) = 0 15:57:04 fcntl(8, F_SETFD, FD_CLOEXEC) = 0 15:57:04 fcntl(8, F_SETLK, {l_type=F_WRLCK, l_whence=SEEK_SET, l_start=0, l_len=0}) = -1 EAGAIN (Risurco dumtempe ne disponeblas) 15:57:04 close(8) = 0 15:57:04 openat(AT_FDCWD, "/gnu/store/5hdpffkgkfszpsin2ir50zscz06x0mb5-coreutils-8.29-debug.lock", O_RDWR|O_CREAT, 0600) = 8 15:57:04 fcntl(8, F_GETFD) = 0 15:57:04 fcntl(8, F_SETFD, FD_CLOEXEC) = 0 15:57:04 fcntl(8, F_SETLK, {l_type=F_WRLCK, l_whence=SEEK_SET, l_start=0, l_len=0}) = -1 EAGAIN (Risurco dumtempe ne disponeblas) 15:57:04 close(8) = 0 15:57:04 openat(AT_FDCWD, "/gnu/store/aasfcliv85frq3aawpa4rw18nvlvl735-gettext-minimal-0.19.8.1.lock", O_RDWR|O_CREAT, 0600) = 8 15:57:04 fcntl(8, F_GETFD) = 0 15:57:04 fcntl(8, F_SETFD, FD_CLOEXEC) = 0 15:57:04 fcntl(8, F_SETLK, {l_type=F_WRLCK, l_whence=SEEK_SET, l_start=0, l_len=0}) = -1 EAGAIN (Risurco dumtempe ne disponeblas) 15:57:04 close(8) = 0 15:57:04 openat(AT_FDCWD, "/gnu/store/j1kpzcpi1m1ihzwyqb60zd4s74yp85g8-glibc-bootstrap-0.lock", O_RDWR|O_CREAT, 0600) = 8 15:57:04 fcntl(8, F_GETFD) = 0 15:57:04 fcntl(8, F_SETFD, FD_CLOEXEC) = 0 15:57:04 fcntl(8, F_SETLK, {l_type=F_WRLCK, l_whence=SEEK_SET, l_start=0, l_len=0}) = -1 EAGAIN (Risurco dumtempe ne disponeblas) 15:57:04 close(8) = 0 15:57:04 openat(AT_FDCWD, "/gnu/store/4llnxsgr6mxxj6pk21d9vbwaxnkbn99k-gnutls-3.5.18-doc.lock", O_RDWR|O_CREAT, 0600) = 8 15:57:04 fcntl(8, F_GETFD) = 0 15:57:04 fcntl(8, F_SETFD, FD_CLOEXEC) = 0 15:57:04 fcntl(8, F_SETLK, {l_type=F_WRLCK, l_whence=SEEK_SET, l_start=0, l_len=0}) = -1 EAGAIN (Risurco dumtempe ne disponeblas) 15:57:04 close(8) = 0 15:57:04 openat(AT_FDCWD, "/gnu/store/7rs9qx86f2w4hjbf9wjm10k4m2vvlbyv-groff-1.22.3-doc.lock", O_RDWR|O_CREAT, 0600) = 8 15:57:04 fcntl(8, F_GETFD) = 0 15:57:04 fcntl(8, F_SETFD, FD_CLOEXEC) = 0 15:57:04 fcntl(8, F_SETLK, {l_type=F_WRLCK, l_whence=SEEK_SET, l_start=0, l_len=0}) = -1 EAGAIN (Risurco dumtempe ne disponeblas) 15:57:04 close(8) = 0 15:57:04 openat(AT_FDCWD, "/gnu/store/d645d919gp1zk8v65qa2r4ia5x1c5n6k-libstdc++-5.5.0.lock", O_RDWR|O_CREAT, 0600) = 8 15:57:04 fcntl(8, F_GETFD) = 0 15:57:04 fcntl(8, F_SETFD, FD_CLOEXEC) = 0 15:57:04 fcntl(8, F_SETLK, {l_type=F_WRLCK, l_whence=SEEK_SET, l_start=0, l_len=0}) = -1 EAGAIN (Risurco dumtempe ne disponeblas) 15:57:04 close(8) = 0 15:57:04 openat(AT_FDCWD, "/gnu/store/amcs7l0ynj1qg6fp9ll3asiamd4zsq75-m4-1.4.18.lock", O_RDWR|O_CREAT, 0600) = 8 15:57:04 fcntl(8, F_GETFD) = 0 15:57:04 fcntl(8, F_SETFD, FD_CLOEXEC) = 0 15:57:04 fcntl(8, F_SETLK, {l_type=F_WRLCK, l_whence=SEEK_SET, l_start=0, l_len=0}) = -1 EAGAIN (Risurco dumtempe ne disponeblas) 15:57:04 close(8) = 0 15:57:04 openat(AT_FDCWD, "/gnu/store/p262qk7zsd2wnlal6x1jax2xbqvdddqq-m4-1.4.18.lock", O_RDWR|O_CREAT, 0600) = 8 15:57:04 fcntl(8, F_GETFD) = 0 15:57:04 fcntl(8, F_SETFD, FD_CLOEXEC) = 0 15:57:04 fcntl(8, F_SETLK, {l_type=F_WRLCK, l_whence=SEEK_SET, l_start=0, l_len=0}) = -1 EAGAIN (Risurco dumtempe ne disponeblas) 15:57:04 close(8) = 0 15:57:04 openat(AT_FDCWD, "/gnu/store/zvvgr301hz95ac15rp0wsjy5j4cdgkg4-module-import-compiled.lock", O_RDWR|O_CREAT, 0600) = 8 15:57:04 fcntl(8, F_GETFD) = 0 15:57:04 fcntl(8, F_SETFD, FD_CLOEXEC) = 0 15:57:04 fcntl(8, F_SETLK, {l_type=F_WRLCK, l_whence=SEEK_SET, l_start=0, l_len=0}) = -1 EAGAIN (Risurco dumtempe ne disponeblas) 15:57:04 close(8) = 0 15:57:04 openat(AT_FDCWD, "/gnu/store/760kj698c9x1vcmlzk1qr8i9hqw961n3-openssl-1.0.2o-doc.lock", O_RDWR|O_CREAT, 0600) = 8 ^C $ sudo strace -p 20503 -t strace: Process 20503 attached 15:58:23 select(445, [15 54 159 177 321 411 414 444], NULL, NULL, {tv_sec=1, tv_usec=595302}) = 0 (Timeout) 15:58:25 openat(AT_FDCWD, "/gnu/store/amcs7l0ynj1qg6fp9ll3asiamd4zsq75-m4-1.4.18.lock", O_RDWR|O_CREAT, 0600) = 14 15:58:25 fcntl(14, F_GETFD) = 0 15:58:25 fcntl(14, F_SETFD, FD_CLOEXEC) = 0 15:58:25 fcntl(14, F_SETLK, {l_type=F_WRLCK, l_whence=SEEK_SET, l_start=0, l_len=0}) = -1 EAGAIN (Risurco dumtempe ne disponeblas) 15:58:25 close(14) = 0 15:58:25 openat(AT_FDCWD, "/gnu/store/zvvgr301hz95ac15rp0wsjy5j4cdgkg4-module-import-compiled.lock", O_RDWR|O_CREAT, 0600) = 14 15:58:25 fcntl(14, F_GETFD) = 0 15:58:25 fcntl(14, F_SETFD, FD_CLOEXEC) = 0 15:58:25 fcntl(14, F_SETLK, {l_type=F_WRLCK, l_whence=SEEK_SET, l_start=0, l_len=0}) = -1 EAGAIN (Risurco dumtempe ne disponeblas) 15:58:25 close(14) = 0 15:58:25 openat(AT_FDCWD, "/gnu/store/760kj698c9x1vcmlzk1qr8i9hqw961n3-openssl-1.0.2o-doc.lock", O_RDWR|O_CREAT, 0600) = 14 15:58:25 fcntl(14, F_GETFD) = 0 15:58:25 fcntl(14, F_SETFD, FD_CLOEXEC) = 0 15:58:25 fcntl(14, F_SETLK, {l_type=F_WRLCK, l_whence=SEEK_SET, l_start=0, l_len=0}) = -1 EAGAIN (Risurco dumtempe ne disponeblas) 15:58:25 close(14) = 0 15:58:25 select(445, [15 54 159 177 321 411 414 444], NULL, NULL, {tv_sec=5, tv_usec=0}) = 0 (Timeout) 15:58:30 openat(AT_FDCWD, "/gnu/store/amcs7l0ynj1qg6fp9ll3asiamd4zsq75-m4-1.4.18.lock", O_RDWR|O_CREAT, 0600) = 14 15:58:30 fcntl(14, F_GETFD) = 0 15:58:30 fcntl(14, F_SETFD, FD_CLOEXEC) = 0 15:58:30 fcntl(14, F_SETLK, {l_type=F_WRLCK, l_whence=SEEK_SET, l_start=0, l_len=0}) = -1 EAGAIN (Risurco dumtempe ne disponeblas) 15:58:30 close(14) = 0 15:58:30 openat(AT_FDCWD, "/gnu/store/zvvgr301hz95ac15rp0wsjy5j4cdgkg4-module-import-compiled.lock", O_RDWR|O_CREAT, 0600) = 14 15:58:30 fcntl(14, F_GETFD) = 0 15:58:30 fcntl(14, F_SETFD, FD_CLOEXEC) = 0 15:58:30 fcntl(14, F_SETLK, {l_type=F_WRLCK, l_whence=SEEK_SET, l_start=0, l_len=0}) = -1 EAGAIN (Risurco dumtempe ne disponeblas) 15:58:30 close(14) = 0 15:58:30 openat(AT_FDCWD, "/gnu/store/760kj698c9x1vcmlzk1qr8i9hqw961n3-openssl-1.0.2o-doc.lock", O_RDWR|O_CREAT, 0600) = 14 15:58:30 fcntl(14, F_GETFD) = 0 15:58:30 fcntl(14, F_SETFD, FD_CLOEXEC) = 0 15:58:30 fcntl(14, F_SETLK, {l_type=F_WRLCK, l_whence=SEEK_SET, l_start=0, l_len=0}) = -1 EAGAIN (Risurco dumtempe ne disponeblas) 15:58:30 close(14) = 0 15:58:30 select(445, [15 54 159 177 321 411 414 444], NULL, NULL, {tv_sec=5, tv_usec=0}^Cstrace: Process 20503 detached $ sudo strace -p 20501 -t strace: Process 20501 attached 15:59:09 select(121, [20 30 120], NULL, NULL, {tv_sec=0, tv_usec=535316}) = 0 (Timeout) 15:59:10 openat(AT_FDCWD, "/gnu/store/ghc9vcc8ydv305jz0spd73qrrf30gxik-binutils-bootstrap-0.lock", O_RDWR|O_CREAT, 0600) = 8 15:59:10 fcntl(8, F_GETFD) = 0 15:59:10 fcntl(8, F_SETFD, FD_CLOEXEC) = 0 15:59:10 fcntl(8, F_SETLK, {l_type=F_WRLCK, l_whence=SEEK_SET, l_start=0, l_len=0}) = -1 EAGAIN (Risurco dumtempe ne disponeblas) 15:59:10 close(8) = 0 15:59:10 openat(AT_FDCWD, "/gnu/store/5hdpffkgkfszpsin2ir50zscz06x0mb5-coreutils-8.29-debug.lock", O_RDWR|O_CREAT, 0600) = 8 15:59:10 fcntl(8, F_GETFD) = 0 15:59:10 fcntl(8, F_SETFD, FD_CLOEXEC) = 0 15:59:10 fcntl(8, F_SETLK, {l_type=F_WRLCK, l_whence=SEEK_SET, l_start=0, l_len=0}) = -1 EAGAIN (Risurco dumtempe ne disponeblas) 15:59:10 close(8) = 0 15:59:10 openat(AT_FDCWD, "/gnu/store/aasfcliv85frq3aawpa4rw18nvlvl735-gettext-minimal-0.19.8.1.lock", O_RDWR|O_CREAT, 0600) = 8 15:59:10 fcntl(8, F_GETFD) = 0 15:59:10 fcntl(8, F_SETFD, FD_CLOEXEC) = 0 15:59:10 fcntl(8, F_SETLK, {l_type=F_WRLCK, l_whence=SEEK_SET, l_start=0, l_len=0}) = -1 EAGAIN (Risurco dumtempe ne disponeblas) 15:59:10 close(8) = 0 15:59:10 openat(AT_FDCWD, "/gnu/store/j1kpzcpi1m1ihzwyqb60zd4s74yp85g8-glibc-bootstrap-0.lock", O_RDWR|O_CREAT, 0600) = 8 15:59:10 fcntl(8, F_GETFD) = 0 15:59:10 fcntl(8, F_SETFD, FD_CLOEXEC) = 0 15:59:10 fcntl(8, F_SETLK, {l_type=F_WRLCK, l_whence=SEEK_SET, l_start=0, l_len=0}) = -1 EAGAIN (Risurco dumtempe ne disponeblas) 15:59:10 close(8) = 0 15:59:10 openat(AT_FDCWD, "/gnu/store/4llnxsgr6mxxj6pk21d9vbwaxnkbn99k-gnutls-3.5.18-doc.lock", O_RDWR|O_CREAT, 0600) = 8 15:59:10 fcntl(8, F_GETFD) = 0 15:59:10 fcntl(8, F_SETFD, FD_CLOEXEC) = 0 15:59:10 fcntl(8, F_SETLK, {l_type=F_WRLCK, l_whence=SEEK_SET, l_start=0, l_len=0}) = -1 EAGAIN (Risurco dumtempe ne disponeblas) 15:59:10 close(8) = 0 15:59:10 openat(AT_FDCWD, "/gnu/store/7rs9qx86f2w4hjbf9wjm10k4m2vvlbyv-groff-1.22.3-doc.lock", O_RDWR|O_CREAT, 0600) = 8 15:59:10 fcntl(8, F_GETFD) = 0 15:59:10 fcntl(8, F_SETFD, FD_CLOEXEC) = 0 15:59:10 fcntl(8, F_SETLK, {l_type=F_WRLCK, l_whence=SEEK_SET, l_start=0, l_len=0}) = -1 EAGAIN (Risurco dumtempe ne disponeblas) 15:59:10 close(8) = 0 15:59:10 openat(AT_FDCWD, "/gnu/store/d645d919gp1zk8v65qa2r4ia5x1c5n6k-libstdc++-5.5.0.lock", O_RDWR|O_CREAT, 0600) = 8 15:59:10 fcntl(8, F_GETFD) = 0 15:59:10 fcntl(8, F_SETFD, FD_CLOEXEC) = 0 15:59:10 fcntl(8, F_SETLK, {l_type=F_WRLCK, l_whence=SEEK_SET, l_start=0, l_len=0}) = -1 EAGAIN (Risurco dumtempe ne disponeblas) 15:59:10 close(8) = 0 15:59:10 openat(AT_FDCWD, "/gnu/store/p262qk7zsd2wnlal6x1jax2xbqvdddqq-m4-1.4.18.lock", O_RDWR|O_CREAT, 0600) = 8 15:59:10 fcntl(8, F_GETFD) = 0 15:59:10 fcntl(8, F_SETFD, FD_CLOEXEC) = 0 15:59:10 fcntl(8, F_SETLK, {l_type=F_WRLCK, l_whence=SEEK_SET, l_start=0, l_len=0}) = -1 EAGAIN (Risurco dumtempe ne disponeblas) 15:59:10 close(8) = 0 15:59:10 select(121, [20 30 120], NULL, NULL, {tv_sec=5, tv_usec=0}^Cstrace: Process 20501 detached $ sudo lsof | grep '/gnu/store/.*\.lock' guix-daem 20501 root 14uW REG 253,0 0 3150879 /gnu/store/zvvgr301hz95ac15rp0wsjy5j4cdgkg4-module-import-compiled.lock guix-daem 20501 root 26uW REG 253,0 0 3212618 /gnu/store/760kj698c9x1vcmlzk1qr8i9hqw961n3-openssl-1.0.2o-doc.lock guix-daem 20501 root 116uW REG 253,0 0 3212684 /gnu/store/amcs7l0ynj1qg6fp9ll3asiamd4zsq75-m4-1.4.18.lock guix-daem 20503 root 8uW REG 253,0 0 3212520 /gnu/store/7rs9qx86f2w4hjbf9wjm10k4m2vvlbyv-groff-1.22.3-doc.lock guix-daem 20503 root 50uW REG 253,0 0 3212514 /gnu/store/ghc9vcc8ydv305jz0spd73qrrf30gxik-binutils-bootstrap-0.lock guix-daem 20503 root 155uW REG 253,0 0 3212547 /gnu/store/j1kpzcpi1m1ihzwyqb60zd4s74yp85g8-glibc-bootstrap-0.lock guix-daem 20503 root 173uW REG 253,0 0 3212552 /gnu/store/4llnxsgr6mxxj6pk21d9vbwaxnkbn99k-gnutls-3.5.18-doc.lock guix-daem 20503 root 317uW REG 253,0 0 3212602 /gnu/store/d645d919gp1zk8v65qa2r4ia5x1c5n6k-libstdc++-5.5.0.lock guix-daem 20503 root 407uW REG 253,0 0 3212655 /gnu/store/5hdpffkgkfszpsin2ir50zscz06x0mb5-coreutils-8.29-debug.lock guix-daem 20503 root 410uW REG 253,0 0 3212659 /gnu/store/aasfcliv85frq3aawpa4rw18nvlvl735-gettext-minimal-0.19.8.1.lock guix-daem 20503 root 440uW REG 253,0 0 3212686 /gnu/store/p262qk7zsd2wnlal6x1jax2xbqvdddqq-m4-1.4.18.lock --8<---------------cut here---------------end--------------->8--- So for example: • 20501 tries to acquire aasfcliv85frq3aawpa4rw18nvlvl735-gettext-minimal-0.19.8.1.lock, which is held by 20503; • 20503 tries to acquire amcs7l0ynj1qg6fp9ll3asiamd4zsq75-m4-1.4.18.lock, which is held by 20501. This comes from the fact that ‘LocalStore::buildPaths’ takes the user-supplied derivation list as is, without sorting it, and then acquires locks in that order in ‘Worker::run’. A topological sort (or maybe an alphanumeric sort?) should allow us to guarantee that guix-daemon processes take locks in the same order, and then don’t end up in a deadlock. I discovered this bug while monitoring Cuirass on berlin: several sessions submit batches of 200 derivations in ‘build-paths’ RPCs, and sometimes most of the corresponding guix-daemon processes would end up being stuck in a lock-acquiring loop. Ludo’.