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On Fri, 21 Feb 2014 16:14:00 +0200, Nikos Chantziaras |
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<realnc@×××××.com> wrote: |
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> I recently needed to unmerge Netbeans and KDE from a machine. So |
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> removed the top-level packages of those, and then ran: |
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> |
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> emerge -a --depclean --jobs 20 |
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> |
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> However, "--jobs" is being ignored. So I'm sitting there, watching |
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> hundreds of packages being unmerged one by one, taking a long time :-/ |
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> |
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> Is this normal? Shouldn't the --jobs option result in emerge |
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> unmerging multiple packages at the same time? |
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> |
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|
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From emerge(1)[1]: |
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-j [JOBS], --jobs[=JOBS] |
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Specifies the number of packages to build |
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simultaneously. (...) |
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|
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In the past, unmerging was almost entirely IO bound, and running |
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several in parallel would have (at best) no significant speedup. I |
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suspect the (fairly recent) preserve-libs feature and detection of |
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unmodified configuration files introduced some cpu-intensive parts, |
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which might be parallelizeable to some extent if you sacrifice some of |
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the recoverability of an aborted unmerge. |
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|
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If you can benchmark low IO utilization during unmerges, I suggest you |
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open a feature request bug on <bugs.gentoo.org> requesting parallel |
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unmerge. :-) |
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|
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In the mean time, you might be able to speed the process up somewhat by |
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setting FEATURES="-merge-sync" in the environment when you do unmerges. |
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(see make.conf(5)[2]) |
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|
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1: https://dev.gentoo.org/~zmedico/portage/doc/man/emerge.1.html |
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2: https://dev.gentoo.org/~zmedico/portage/doc/man/make.conf.5.html |
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|
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-- |
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eroen |