8 ms·

Have they solved the performance issue in any way?

pjmlp 7y ago
QNX, L4 and Minix 3 have solved it ages ago. Even current macOS variants do plenty of message passing and sandboxing. From the iOS games and real time audio apps, it appears fast enough to me.
- rurban 7y ago
  But they are fundamentally different. They have no mailboxes in the server, they just pass the messages through to the right client after some capabilities check. Mach and Hurd on the other hand store the messages in the kernel, priorities them and handles all mailbox messages, without ever losing one. This proved to be the wrong approach.
  - pjmlp 7y ago
    Seems to work alright for consumer media in real time, something that monolithic Linux has real issues with.
    - seabrookmx 7y ago
      I think that just goes to show that when it comes to consumer media, there's probably more important layers in the stack that should be the focus of optimizations. Lack of hardware acceleration, and the general clunkiness of X windows make Linux crappy in this regard for example. I _still_ get screen tearing in Ubuntu 18.04 if I don't run Wayland, which I don't because it breaks some apps I use.
    - rurban 7y ago
      For consumer media it's even more important to drop late or lost messages. Just like with its transport protocol RTP or UDP. A microkernel is much, much simplier than those protocols.
- panpanna 7y ago
  There are no proper L4 performance comparisons. A few benchmark L4Linux, where L4 is not used as a microkernel but a hypervisor which consequently proves nothing about the micokernel paradigm.
  - pjmlp 7y ago
    An hypervisor is a kind of microkernel. The benchmark is its use as radio OS on many handsets.
    - panpanna 7y ago
      Yes, but... This usage goes against many of the security claims of microkernels. In particular. If Linux is big and insecure running it in a VM doesn't really improves its security. It just make sure it doesn't infect the rest of the system. For this type of benchmark the "rest of the system" does not exist. (I assume you meant the baseband processor in iPhone and Android. I don't think either use a clean microkernel and there isn't really a performance comparison available)
      - pjmlp 7y ago
        I prefer to see hypervisors used alongside Unikernels in what concerns security. For me the benchmark that counts is "does it deliver in production", winning ms in laboratory micro-benchmarks is kind of useless. Specially when so many are willing to waste those ms running Electron apps on userspace.
  - mcguire 7y ago
    I've forgotten it's title, but there was a performance comparison between Linux and MkLinux (with the OSF/Mach microkernel) in the one and only FSF free software conference. It had my favorite chart: a barchart showing the relative performance. The top half was 1:1; the bottom half was 1:2 or so. The top half was Dhrystones (CPU integer performance), the bottom was various syscalls.
  - snvzz 7y ago
    Section 2.1, table 1:4. https://ts.data61.csiro.au/publications/nicta_full_text/8988.pdf https://ts.data61.csiro.au/publications/nicta_full_text/8988...

QNX, L4 and Minix 3 have solved it ages ago. Even current macOS variants do plenty of message passing and sandboxing. From the iOS games and real time audio apps, it appears fast enough to me.

rurban 7y ago
But they are fundamentally different. They have no mailboxes in the server, they just pass the messages through to the right client after some capabilities check. Mach and Hurd on the other hand store the messages in the kernel, priorities them and handles all mailbox messages, without ever losing one. This proved to be the wrong approach.
- pjmlp 7y ago
  Seems to work alright for consumer media in real time, something that monolithic Linux has real issues with.
  - seabrookmx 7y ago
    I think that just goes to show that when it comes to consumer media, there's probably more important layers in the stack that should be the focus of optimizations. Lack of hardware acceleration, and the general clunkiness of X windows make Linux crappy in this regard for example. I _still_ get screen tearing in Ubuntu 18.04 if I don't run Wayland, which I don't because it breaks some apps I use.
  - rurban 7y ago
    For consumer media it's even more important to drop late or lost messages. Just like with its transport protocol RTP or UDP. A microkernel is much, much simplier than those protocols.
panpanna 7y ago
There are no proper L4 performance comparisons. A few benchmark L4Linux, where L4 is not used as a microkernel but a hypervisor which consequently proves nothing about the micokernel paradigm.
- pjmlp 7y ago
  An hypervisor is a kind of microkernel. The benchmark is its use as radio OS on many handsets.
  - panpanna 7y ago
    Yes, but... This usage goes against many of the security claims of microkernels. In particular. If Linux is big and insecure running it in a VM doesn't really improves its security. It just make sure it doesn't infect the rest of the system. For this type of benchmark the "rest of the system" does not exist. (I assume you meant the baseband processor in iPhone and Android. I don't think either use a clean microkernel and there isn't really a performance comparison available)
    - pjmlp 7y ago
      I prefer to see hypervisors used alongside Unikernels in what concerns security. For me the benchmark that counts is "does it deliver in production", winning ms in laboratory micro-benchmarks is kind of useless. Specially when so many are willing to waste those ms running Electron apps on userspace.
- mcguire 7y ago
  I've forgotten it's title, but there was a performance comparison between Linux and MkLinux (with the OSF/Mach microkernel) in the one and only FSF free software conference. It had my favorite chart: a barchart showing the relative performance. The top half was 1:1; the bottom half was 1:2 or so. The top half was Dhrystones (CPU integer performance), the bottom was various syscalls.
- snvzz 7y ago
  Section 2.1, table 1:4. https://ts.data61.csiro.au/publications/nicta_full_text/8988.pdf https://ts.data61.csiro.au/publications/nicta_full_text/8988...