4 ms·

I had Gentoo running on an old PPC (old grey Mac) back around 2010 and it booted in just a minute or two. If you watch the video, it gets past the kernel boot

I had Gentoo running on an old PPC (old grey Mac) back around 2010 and it booted in just a minute or two. If you watch the video, it gets past the kernel boot stage in under a minute. OpenRC seems to be stalling for a bit on calculating/caching dependencies. That really shouldn't take that long. I wonder how many services he has enabled or if there's some regression introduced there. Then it takes forever to mount certain things like shared memory, cgroups, SELinux, etc. Granted I didn't have cgroups, SELinux or most of this stuff back when I ran Gentoo on that PPC. I kinda wish my dad hadn't thrown it out. I wonder what it would be like to put modern Gentoo on it. I wonder if I'd get similar slowdown. If you tweeked this init system, or ran a more embedded distribution, the boot time would only be about a minute.

yeokm1 9y ago
I agree that I could have optimised the system more. Since this is the first time I'm installing Gentoo, I just followed the default instructions given in the Gentoo Handbook. https://wiki.gentoo.org/wiki/Handbook:X86 https://wiki.gentoo.org/wiki/Handbook:X86
exikyut 9y ago
My guess is CF slowness.
- yeokm1 9y ago
  The CF card is a Sandisk Extreme with up to 120MB/s read speed. My guess is the PATA interface on that motherboard is also a bottleneck. I did a disk speed test with "dd if=/dev/zero of=/tmp/output bs=8k count=2k" I only got 720KB/s.
  - exikyut 9y ago
    TIL! Interesting benchmark. I'd recommend trying bs=256k, which is what Linux is optimized for FWIW. 8k may induce overhead, but I can't say for sure how much of a difference 256k would make. I just briefly poked eBay to find out the price of ISA disk controllers, and found a reasonable number of options within the <$30 bracket. https://www.ebay.com/b/ISA-Internal-Disk-Controllers-RAID-Cards/90715/bn_2785081?rt=nc&_sop=15&_fcid=180 https://www.ebay.com/b/ISA-Internal-Disk-Controllers-RAID-Ca... The nice thing is that Linux will (almost certainly?) have no problem no matter what card you buy, so the question is what the fastest chipset is. I also just found https://wiki.68kmla.org/SCSI_hard_disk_replacement_options#IDE_and_Flash https://wiki.68kmla.org/SCSI_hard_disk_replacement_options#I... which may prove relevant.
    - yeokm1 9y ago
      Ok I can give 256K a shot next time. Actually won't the ISA controllers be even slower? I'm not sure what bus the PATA controllers on this PC are connected to but isn't it connected "natively" so to speak? It might even compete for bandwidth with the sound and network card.
      - exikyut 9y ago
        Very, very good point. I'm not sure. Don't quote me, but I think the onboard PATA controller is connected via ISA as well.
        yeokm1 9y ago
        Very likely the onboard PATA controller is connected via ISA. I had to enable the ISA PATA support during the kernel configuration for Linux to recognise it. In this case, there probably won't be any benefit of having additional ISA controller cards.
        exikyut 9y ago
        This is very very possible. What I wonder is whether the onboard chipset is slower than the ISA bus - and whether using an external card would eke out a tiny bit more performance. Apparently the ISA bus can stably run at up to 8MHz. It's not on-point but I found this thread that discussed SCSI controllers that was kind of interesting: http://www.vogons.org/viewtopic.php?t=36001 http://www.vogons.org/viewtopic.php?t=36001 This project is really awesome btw.

yeokm1 9y ago

I agree that I could have optimised the system more. Since this is the first time I'm installing Gentoo, I just followed the default instructions given in the Gentoo Handbook. https://wiki.gentoo.org/wiki/Handbook:X86 https://wiki.gentoo.org/wiki/Handbook:X86

exikyut 9y ago

My guess is CF slowness.

yeokm1 9y ago
The CF card is a Sandisk Extreme with up to 120MB/s read speed. My guess is the PATA interface on that motherboard is also a bottleneck. I did a disk speed test with "dd if=/dev/zero of=/tmp/output bs=8k count=2k" I only got 720KB/s.
- exikyut 9y ago
  TIL! Interesting benchmark. I'd recommend trying bs=256k, which is what Linux is optimized for FWIW. 8k may induce overhead, but I can't say for sure how much of a difference 256k would make. I just briefly poked eBay to find out the price of ISA disk controllers, and found a reasonable number of options within the <$30 bracket. https://www.ebay.com/b/ISA-Internal-Disk-Controllers-RAID-Cards/90715/bn_2785081?rt=nc&_sop=15&_fcid=180 https://www.ebay.com/b/ISA-Internal-Disk-Controllers-RAID-Ca... The nice thing is that Linux will (almost certainly?) have no problem no matter what card you buy, so the question is what the fastest chipset is. I also just found https://wiki.68kmla.org/SCSI_hard_disk_replacement_options#IDE_and_Flash https://wiki.68kmla.org/SCSI_hard_disk_replacement_options#I... which may prove relevant.
  - yeokm1 9y ago
    Ok I can give 256K a shot next time. Actually won't the ISA controllers be even slower? I'm not sure what bus the PATA controllers on this PC are connected to but isn't it connected "natively" so to speak? It might even compete for bandwidth with the sound and network card.
    - exikyut 9y ago
      Very, very good point. I'm not sure. Don't quote me, but I think the onboard PATA controller is connected via ISA as well.
      - yeokm1 9y ago
        Very likely the onboard PATA controller is connected via ISA. I had to enable the ISA PATA support during the kernel configuration for Linux to recognise it. In this case, there probably won't be any benefit of having additional ISA controller cards.
        exikyut 9y ago
        This is very very possible. What I wonder is whether the onboard chipset is slower than the ISA bus - and whether using an external card would eke out a tiny bit more performance. Apparently the ISA bus can stably run at up to 8MHz. It's not on-point but I found this thread that discussed SCSI controllers that was kind of interesting: http://www.vogons.org/viewtopic.php?t=36001 http://www.vogons.org/viewtopic.php?t=36001 This project is really awesome btw.