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<azert>I understood that migrating threads were mostly a resource accounting tool. But yes, I understand that this optimization might not be implemented but it seems important since if not there will be lots of dispatching and cache faults for no gain

<youpi>migrating threads are useful to account expenses, yes

<youpi>but that's also useful for locality in the end

<azert>Ah, the migrating thread data structures was probably where this information could be passed along the layers

<solid_black>good morning

<damo22>good evening

<solid_black>:)

<solid_black>so does ext2fs run w/ smp now?

<damo22>i havent tried

<damo22>i mean, it runs in cpu0

<damo22>and works with slave_pset sending requests to it

<solid_black>yeah, but let's try to run it on full smp?

<solid_black>and debug any issues that come up

<youpi>better run a second ext2fs in the pset, not the / ext2fs ;)

<solid_black>that'd be a good start, yeah

<solid_black>a second ./smp /hurd/ext2fs, and run a -j8 build on that

<damo22>can it work as a translator entry?

<youpi>and fsck it after doing so

<youpi>to check that it really didn't get wrong :)

<youpi>damo22: I was thinking about it, I believe so

<youpi>since execve keeps all ports etc. intact

<solid_black>yes

<solid_black>at least rpctrace does work

<youpi>if ext2fs works really badly, perhaps try a simpler translator for

<youpi>such as fatfs or such

<damo22>do i need to create a smp storeio?

<youpi>testing storio is a separate question :)

<solid_black>indeed

<youpi>note anyway that storeio is just a proxy for the information

<youpi>ext2fs then doesn't use it

<youpi>see the bypass in libstoreio

<youpi>that gets the storage information from storeio, then directly access the underlying data

<damo22>i dont know how to mount with settrans

<youpi>settrans /mnt/mnt /hurd/ext2fs /my/disk/image.img

<youpi>if you want an active mount, add -a

<solid_black>settrans -ac, rather

<youpi>settrans -a /mnt/mnt /hurd/ext2fs /my/disk/image.img

<youpi>-c if /mnt/mnt doesn't exist yet, yes

<youpi>is there a limit on the number of processors? (because of e.g. cpumask or such)

<youpi>there are machines here in the lab with 64 hyperthreaded cores, so I can stress this "a bit" :)

<solid_black> https://xkcd.com/619/

<youpi>heh :D

<damo22>root@zamhurd:~# e2fsck -y /dev/wd0s3

<damo22>e2fsck 1.46.6 (1-Feb-2023)

<damo22>/dev/wd0s3: clean, 616200/3276800 files, 6413347/13107200 blocks

<solid_black>-f

<damo22>that was after a -j8 build

<youpi>use -f, yes

<solid_black>but the build succeeded?

<damo22>yes

<youpi>so is fsck fine with -f ?

<damo22>and ext2fs used 125% cpu at one point

<youpi>I was wondering whether top was displaying such stats correctly, so it does?

<youpi>does the per-cpu stats work too?

<youpi>(when typing 1)

<damo22>no

<damo22>the per cpu stats dont work

<damo22>but it displays % correctly

<youpi>ok, that'd be useful to fix :)

<solid_black>does top read /proc, or does it use something Hurd-spcific?

<youpi>it's probably not hard

<youpi>it uses /proc

<youpi>so it's procfs to be fixed

<damo22>-fy completed with no errors

<solid_black>🎉️

<youpi>yay

<damo22>i mounted the disk with settrans -a /part3 /home/demo/bin/smp /hurd/ext2fs /dev/wd0s3

<solid_black>time to try root / with smp then :D

<youpi>there's also the "last cpu used" columns which would be interesting to fix

<youpi>I don't remember what top uses to get that though

<damo22>how do i build a debian package with -j8

<solid_black>doesn't it do that by default?

<damo22>i want to try building rumpkernel

<damo22>the problem with ./smp is that it needs root

<youpi>DEB_BUILD_OPTIONS=parallel=8

<youpi>export that

<solid_black>./smp sudo --user=me make?

<youpi>normally it uses nproc

<solid_black>and nproc is 8

<damo22>ok

<youpi>but at worse you can force with that

<damo22>i end up doing

<damo22># ./smp /bin/bash

<damo22># su demo

<damo22>$ make -j8

<damo22>it would be nice to be able to drop privileges to another user in one command

<youpi>you can combine it all

<youpi>sudo ./smp su demo make -j 8

<youpi>module some options

<youpi>to tell su that it's make -j 8 you want to run

<solid_black>(yay unix)

<damo22>heh

<solid_black>also on teh Hurd specifically, you can have root (or other) privileges without it being your euid

<damo22>sudo ./smp su demo -c make -j8

<solid_black>so e.g. any files will be created as 'demo', but you will have all the access that 'root' has (including host priv port)

<solid_black>could you also measure the time it takes?

<solid_black>i.e. time make; make clean; time make -j8

<damo22>$ sudo /home/demo/bin/smp /usr/bin/su demo -c "make -j8"

<solid_black>really, just do $ addauth --pid=$$ root

<solid_black>and drop all the sudo/su

<solid_black>actually we should only need to keep copies of the first and the last vm entry in the address range

<solid_black>so no need for alloca

<solid_black>also there's the entry->in_transition mechanism, looks like it's supposed to be used for cases like ours

<gnucode>Am I reading the logs right? Ya'll got ext2fs working vis SMP ?

<sneek>gnucode, you have 1 message!

<sneek>gnucode, nckx says: No, but I'd be happy to create one if useful.

<youpi>gnucode: yes, apparently it's all fine without any fixes inside ext2fs

<gnucode>that's pretty awesome!

IRC channel logs

2024-02-22.log