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2014 can be like stone age if you think a new kernel release gets released less than every 90 days. On the other hand development of some features just takes lo

2014 can be like stone age if you think a new kernel release gets released less than every 90 days. On the other hand development of some features just takes longer and longer than ever expected (not a surprise for any developer). Well, stone age at least if you run a bit more fresh distro than some CentOS or oldstable Debian. So are typical modern desktop Linuxes tickless already or not yet?

usr1106 4y ago
Answering to myself. From Ubuntu 20.04 generic kernel 5.13: CONFIG_NO_HZ_COMMON=y # CONFIG_HZ_PERIODIC is not set CONFIG_NO_HZ_IDLE=y # CONFIG_NO_HZ_FULL is not set CONFIG_NO_HZ=y # CONFIG_HZ_100 is not set CONFIG_HZ_250=y # CONFIG_HZ_300 is not set # CONFIG_HZ_1000 is not set CONFIG_HZ=250 Without looking up all details now I guess CONFIG_NO_HZ_IDLE=y means tickless when idle? That's of course not a very new kernel. Archlinux has 5.18, but don't have my machine accessible at this moment.
- metadat 4y ago
  5.13 is pretty recent...in fact any 5.x is super up to date, still tons of 3.x and 4.x kernels running out there in the wild, wild real world.
  - dmd 4y ago
    3? Try 2. Linux my-host-name-here 2.6.18-128.el5 #1 SMP Wed Dec 17 11:41:38 EST 2008 x86_64 x86_64 x86_64 GNU/Linux Nearly all the (medical instrument) hardware where I work (a major hospital) is on 2.x, mostly running RHEL 5.
    - usr1106 4y ago
      One would assume that medical device vendors could pay for extended support. However, even extended support for HEL 5 has ended now. And even before that in heavily regulated industry that uses such old stuff I would assume rolling out updates is a very slow progress. Maybe not all that stuff connects to the internet, but I bet an ever increasing share does. So hospitals might have wose firewalls than others, so I would not surprised about such equipment being successfully attacked. Of course old versions are unaffected because by newly introduced vulnerabilities. But old ones that have existed "forever" get detected. I guess it's not the kernal alone that is so old, but user space, too.
- 5e92cb50239222b 4y ago
  Arch, 5.18.7 $ zgrep -E '^CONFIG\w*_HZ' /proc/config.gz CONFIG_NO_HZ_COMMON=y CONFIG_NO_HZ_IDLE=y CONFIG_NO_HZ=y CONFIG_HZ_300=y CONFIG_HZ=300 It's been that way for years, I remember seeing that since at least 2015. LWN seems to confirm that feeling: https://lwn.net/Articles/549580/ https://lwn.net/Articles/549580/ > In 3.10, the CONFIG_NO_HZ option has been replaced by a three-way choice: > CONFIG_NO_HZ_IDLE (the default setting) … https://en.wikipedia.org/wiki/Linux_kernel_version_history https://en.wikipedia.org/wiki/Linux_kernel_version_history 3.10 30 June 2013
deleted 4y ago
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usr1106 4y ago

Answering to myself. From Ubuntu 20.04 generic kernel 5.13: CONFIG_NO_HZ_COMMON=y # CONFIG_HZ_PERIODIC is not set CONFIG_NO_HZ_IDLE=y # CONFIG_NO_HZ_FULL is not set CONFIG_NO_HZ=y # CONFIG_HZ_100 is not set CONFIG_HZ_250=y # CONFIG_HZ_300 is not set # CONFIG_HZ_1000 is not set CONFIG_HZ=250 Without looking up all details now I guess CONFIG_NO_HZ_IDLE=y means tickless when idle? That's of course not a very new kernel. Archlinux has 5.18, but don't have my machine accessible at this moment.

metadat 4y ago
5.13 is pretty recent...in fact any 5.x is super up to date, still tons of 3.x and 4.x kernels running out there in the wild, wild real world.
- dmd 4y ago
  3? Try 2. Linux my-host-name-here 2.6.18-128.el5 #1 SMP Wed Dec 17 11:41:38 EST 2008 x86_64 x86_64 x86_64 GNU/Linux Nearly all the (medical instrument) hardware where I work (a major hospital) is on 2.x, mostly running RHEL 5.
  - usr1106 4y ago
    One would assume that medical device vendors could pay for extended support. However, even extended support for HEL 5 has ended now. And even before that in heavily regulated industry that uses such old stuff I would assume rolling out updates is a very slow progress. Maybe not all that stuff connects to the internet, but I bet an ever increasing share does. So hospitals might have wose firewalls than others, so I would not surprised about such equipment being successfully attacked. Of course old versions are unaffected because by newly introduced vulnerabilities. But old ones that have existed "forever" get detected. I guess it's not the kernal alone that is so old, but user space, too.
5e92cb50239222b 4y ago
Arch, 5.18.7 $ zgrep -E '^CONFIG\w*_HZ' /proc/config.gz CONFIG_NO_HZ_COMMON=y CONFIG_NO_HZ_IDLE=y CONFIG_NO_HZ=y CONFIG_HZ_300=y CONFIG_HZ=300 It's been that way for years, I remember seeing that since at least 2015. LWN seems to confirm that feeling: https://lwn.net/Articles/549580/ https://lwn.net/Articles/549580/ > In 3.10, the CONFIG_NO_HZ option has been replaced by a three-way choice: > CONFIG_NO_HZ_IDLE (the default setting) … https://en.wikipedia.org/wiki/Linux_kernel_version_history https://en.wikipedia.org/wiki/Linux_kernel_version_history 3.10 30 June 2013

deleted 4y ago

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