Your message dated Wed, 26 Nov 2008 15:11:26 +0200 with message-id <492D4AFE.8030706@gmail.com> and subject line closing #409872 has caused the Debian Bug report #409872, regarding On slow arch apt just wastes cpu while waiting for dpkg to run to be marked as done. This means that you claim that the problem has been dealt with. If this is not the case it is now your responsibility to reopen the Bug report if necessary, and/or fix the problem forthwith. (NB: If you are a system administrator and have no idea what this message is talking about, this may indicate a serious mail system misconfiguration somewhere. Please contact owner@bugs.debian.org immediately.) -- 409872: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=409872 Debian Bug Tracking System Contact owner@bugs.debian.org with problems
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- To: Debian Bug Tracking System <submit@bugs.debian.org>
- Subject: On slow arch apt just wastes cpu while waiting for dpkg to run
- From: Brian Brunswick <bdb-reportbug@forbidden.co.uk>
- Date: Tue, 06 Feb 2007 02:36:07 +0000
- Message-id: <20070206023607.10448.78382.reportbug@LKG8A754B.example.org>
Package: apt Version: 0.6.46.4 Severity: normal I'm running apt from an nfs-mounted chroot of the real disk inside a qemu-system-arm instance. This is quite slow, but better than the real machine (nslu2) which has infeasibly little memory (32MB) [When I was young...], at least for modern big package databases. However, I notice that while dpkg is running to decompress something, apt is still taking about as much cpu as the dpkg instance. This is sad, giving that all its doing is waiting. strace reveals: .... read(4, 0xbea58906, 1) = -1 EAGAIN (Resource temporarily unavailable) nanosleep({0, 1000000}, NULL) = 0 wait4(12980, 0xbea58758, WNOHANG, NULL) = 0 read(4, 0xbea58906, 1) = -1 EAGAIN (Resource temporarily unavailable) nanosleep({0, 1000000}, NULL) = 0 .... So its got a wait4 and a 1ms delay. A real ARM chip is a disaster on context switches (need to flush the cache - it uses virtual addresses.) I guess qemu-ed it is as well. So I guess I'm asking for this particular bit of code to be fixed to be a bit more gentle. There shouldn't be much slowdown on faster arches, and it could double the speed in this case. Maybe it could do a smart backoff or something. Or indeed just 10ms instead of 1ms would be enough. -- Package-specific info: -- apt-config dump -- APT ""; APT::Architecture "arm"; APT::Build-Essential ""; APT::Build-Essential:: "build-essential"; APT::Authentication ""; APT::Authentication::TrustCDROM "true"; Dir "/"; Dir::State "var/lib/apt/"; Dir::State::lists "lists/"; Dir::State::cdroms "cdroms.list"; Dir::State::userstatus "status.user"; Dir::State::status "/var/lib/dpkg/status"; Dir::Cache "var/cache/apt/"; Dir::Cache::archives "archives/"; Dir::Cache::srcpkgcache "srcpkgcache.bin"; Dir::Cache::pkgcache "pkgcache.bin"; Dir::Etc "etc/apt/"; Dir::Etc::sourcelist "sources.list"; Dir::Etc::sourceparts "sources.list.d"; Dir::Etc::vendorlist "vendors.list"; Dir::Etc::vendorparts "vendors.list.d"; Dir::Etc::main "apt.conf"; Dir::Etc::parts "apt.conf.d"; Dir::Etc::preferences "preferences"; Dir::Bin ""; Dir::Bin::methods "/usr/lib/apt/methods"; Dir::Bin::dpkg "/usr/bin/dpkg"; DPkg ""; DPkg::Pre-Install-Pkgs ""; DPkg::Pre-Install-Pkgs:: "/usr/bin/apt-listchanges --apt || test $? -ne 10"; DPkg::Pre-Install-Pkgs:: "/usr/sbin/dpkg-preconfigure --apt || true"; DPkg::Tools ""; DPkg::Tools::Options ""; DPkg::Tools::Options::/usr/bin/apt-listchanges ""; DPkg::Tools::Options::/usr/bin/apt-listchanges::Version "2"; -- (no /etc/apt/preferences present) -- -- /etc/apt/sources.list -- deb http://ftp.uk.debian.org/debian/ etch main #deb http://debian.hands.com/debian/ sid main #deb-src http://ftp.uk.debian.org/debian/ etch main deb http://security.debian.org/ etch/updates main #deb-src http://security.debian.org/ etch/updates main -- System Information: Debian Release: 4.0 APT prefers testing APT policy: (500, 'testing') Architecture: arm (armv5tel) Shell: /bin/sh linked to /bin/bash Kernel: Linux 2.6.18-3-ixp4xx Locale: LANG=C, LC_CTYPE=C (charmap=ANSI_X3.4-1968) Versions of packages apt depends on: ii debian-archive-keyring 2006.11.22 GnuPG archive keys of the Debian a ii libc6 2.3.6.ds1-10 GNU C Library: Shared libraries ii libgcc1 1:4.1.1-21 GCC support library ii libstdc++6 4.1.1-21 The GNU Standard C++ Library v3 apt recommends no packages. -- no debconf information
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--- Begin Message ---
- To: 409872-done@bugs.debian.org
- Subject: closing #409872
- From: "Eugene V. Lyubimkin" <jackyf.devel@gmail.com>
- Date: Wed, 26 Nov 2008 15:11:26 +0200
- Message-id: <492D4AFE.8030706@gmail.com>
Version: 0.7.7 I guess this is fixed in apt 0.7.7, as modern apt contains no any usleep's while waiting for dpkg. I am closing this bug now, please reopen if needed. -- Eugene V. Lyubimkin aka JackYF, JID: jackyf.devel(maildog)gmail.com Ukrainian C++ Developer, Debian APT contributorAttachment: signature.asc
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