ghc runtime by default (otherwise depending on a "configure" option) does memory allocation on their own by first mmapping a 1 TB range of memory into the process and then parceling out chunks from it. If one of the chunks is not needed, the kernel needs to be informed - otherwise the system would quickly run out of available RAM. ghc does that via madvise(2). There are two options when doing this informing: MADV_FREE - Means "I don't need this range or the data in it any more". Kernel promises to fail later accesses to it. MADV_DONTNEED - Means "I don't need this range right now - and I don't need the data in it anymore". Kernel promises to make later accesses to it succeed (if necessary by providing a new page initialized with zeroes). MADV_FREE was introduced in Linux 4.5. glibc 2.25 and later always define MADV_FREE. Unpatched ghc 8.0.2 will use either MADV_FREE or MADV_DONTNEED, determined at ghc compile time. Which of them will actually succeed is determined by the Linux kernel at run time. This patch makes ghc try MADV_FREE. If it doesn't work, it falls back to MADV_DONTNEED. The end result is that ghc programs free their memory with Linux < 4.5 again. See https://git.haskell.org/ghc.git/commitdiff/6576bf83cdf4eac05eb88a24aa934a736c91e3da for more information. --- a/rts/posix/OSMem.c +++ b/rts/posix/OSMem.c @@ -541,11 +541,24 @@ void osDecommitMemory(void *at, W_ size) #ifdef MADV_FREE // Try MADV_FREE first, FreeBSD has both and MADV_DONTNEED - // just swaps memory out + // just swaps memory out. Linux >= 4.5 has both DONTNEED and FREE; either + // will work as they both allow the system to free anonymous pages. + // It is important that we try both methods as the kernel which we were + // built on may differ from the kernel we are now running on. r = madvise(at, size, MADV_FREE); -#else - r = madvise(at, size, MADV_DONTNEED); + if(r < 0) { + if (errno == EINVAL) { + // Perhaps the system doesn't support MADV_FREE; fall-through and + // try MADV_DONTNEED. + } else { + sysErrorBelch("unable to decommit memory"); + } + } else { + return; + } #endif + + r = madvise(at, size, MADV_DONTNEED); if(r < 0) sysErrorBelch("unable to decommit memory"); } b80f097e092ab4784eb9b2f6197e5d95'>singularity.scm
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2021-09-26tests: Reduce boilerplate for users of 'system-test-runner'....* gnu/tests/audio.scm, gnu/tests/base.scm, gnu/tests/ci.scm, gnu/tests/cups.scm, gnu/tests/databases.scm, gnu/tests/desktop.scm, gnu/tests/dict.scm, gnu/tests/docker.scm, gnu/tests/file-sharing.scm, gnu/tests/ganeti.scm, gnu/tests/guix.scm, gnu/tests/ldap.scm, gnu/tests/linux-modules.scm, gnu/tests/mail.scm, gnu/tests/messaging.scm, gnu/tests/monitoring.scm, gnu/tests/networking.scm, gnu/tests/nfs.scm, gnu/tests/package-management.scm, gnu/tests/reconfigure.scm, gnu/tests/rsync.scm, gnu/tests/security-token.scm, gnu/tests/singularity.scm, gnu/tests/ssh.scm, gnu/tests/telephony.scm, gnu/tests/version-control.scm, gnu/tests/virtualization.scm, gnu/tests/web.scm: Remove (mkdir #$output) (chdir #$output) and pass #$output as argument to 'system-test-runner'. Ludovic Courtès
2021-09-25tests: Adjust to SRFI-64 as found in Guile 3.0.7....In Guile 3.0.7, 'test-runner-current' is set to #f upon 'test-end'. Consequently, the previous strategy, where we'd call 'test-runner-current' after 'test-end', no longer works. Instead, set the test runner in each test right before 'test-begin'. * gnu/build/marionette.scm (system-test-runner): New procedure. * gnu/tests/audio.scm (run-mpd-test): Replace (exit (= ...)) idiom by (test-runner-current (system-test-runner)). * gnu/tests/base.scm (run-basic-test) (run-cleanup-test, run-mcron-test, run-nss-mdns-test): Likewise. * gnu/tests/ci.scm (run-laminar-test): Likewise. * gnu/tests/cups.scm (run-cups-test): Likewise. * gnu/tests/databases.scm (run-memcached-test) (run-postgresql-test, run-mysql-test): Likewise. * gnu/tests/desktop.scm (run-elogind-test): Likewise. * gnu/tests/dict.scm (run-dicod-test): Likewise. * gnu/tests/docker.scm (run-docker-test): Likewise. (run-docker-system-test): Likewise. * gnu/tests/file-sharing.scm (run-transmission-daemon-test): Likewise. * gnu/tests/ganeti.scm (run-ganeti-test): Likewise. * gnu/tests/guix.scm (run-guix-build-coordinator-test): Likewise. (run-guix-data-service-test): Likewise. * gnu/tests/ldap.scm (run-ldap-test): Likewise. * gnu/tests/linux-modules.scm (run-loadable-kernel-modules-test-base): Likewise. * gnu/tests/mail.scm (run-opensmtpd-test) (run-exim-test, run-dovecot-test, run-getmail-test): Likewise. * gnu/tests/messaging.scm (run-xmpp-test) (run-bitlbee-test, run-quassel-test): Likewise. * gnu/tests/monitoring.scm (run-prometheus-node-exporter-server-test) (run-zabbix-server-test): Likewise. * gnu/tests/networking.scm (run-inetd-test, run-openvswitch-test) (run-dhcpd-test, run-tor-test, run-iptables-test, run-ipfs-test): Likewise. * gnu/tests/nfs.scm (run-nfs-test) (run-nfs-server-test, run-nfs-root-fs-test): Likewise. * gnu/tests/package-management.scm (run-nix-test): Likewise. * gnu/tests/reconfigure.scm (run-switch-to-system-test) (run-upgrade-services-test, run-install-bootloader-test): Likewise. * gnu/tests/rsync.scm (run-rsync-test): Likewise. * gnu/tests/security-token.scm (run-pcscd-test): Likewise. * gnu/tests/singularity.scm (run-singularity-test): Likewise. * gnu/tests/ssh.scm (run-ssh-test): Likewise. * gnu/tests/telephony.scm (run-jami-test): Likewise. * gnu/tests/version-control.scm (run-cgit-test): Likewise. (run-git-http-test, run-gitolite-test, run-gitile-test): Likewise. * gnu/tests/virtualization.scm (run-libvirt-test, run-childhurd-test): Likewise. * gnu/tests/web.scm (run-webserver-test, run-php-fpm-test) (run-hpcguix-web-server-test, run-tailon-test, run-patchwork-test): Likewise. Ludovic Courtès