Arch Linux User Repository

This package have several variables to enable/disable features.

##
## The following variables can be customized at build time. Use env or export to change at your wish
##
##   Example: env _microarchitecture=98 use_numa=n use_tracers=n makepkg -sc
##
## Look inside 'choose-gcc-optimization.sh' to choose your microarchitecture
## Valid numbers between: 0 to 99
## Default is: 0 => generic
## Good option if your package is for one machine: 98 (Intel native) or 99 (AMD native)
if [ -z ${_microarchitecture+x} ]; then
  _microarchitecture=0
fi

## Disable NUMA since most users do not have multiple processors. Breaks CUDA/NvEnc.
## Archlinux and Xanmod enable it by default.
## Set variable "use_numa" to: n to disable (possibly increase performance)
##                             y to enable  (stock default)
if [ -z ${use_numa+x} ]; then
  use_numa=y
fi

## Since upstream disabled CONFIG_STACK_TRACER (limits debugging and analyzing of the kernel)
## you can enable them setting this option. Caution, because they have an impact in performance.
## Stock Archlinux has this enabled. 
## Set variable "use_tracers" to: n to disable (possibly increase performance, XanMod default)
##                                y to enable  (Archlinux default)
if [ -z ${use_tracers+x} ]; then
  use_tracers=n
fi

# Unique compiler supported upstream is GCC
## Choose between GCC and CLANG config (default is GCC)
## Use the environment variable "_compiler=clang"
if [ "${_compiler}" = "clang" ]; then
  _compiler_flags="CC=clang HOSTCC=clang LLVM=1 LLVM_IAS=1"
fi

# Choose between the 4 main configs for stable branch. Default x86-64-v1 which use CONFIG_GENERIC_CPU2:
# Possible values: config_x86-64-v1 (default) / config_x86-64-v2 / config_x86-64-v3 / config_x86-64-v4
# This will be overwritten by selecting any option in microarchitecture script
# Source files: https://github.com/xanmod/linux/tree/5.17/CONFIGS/xanmod/gcc
if [ -z ${_config+x} ]; then
  _config=config_x86-64-v1
fi

# Compress modules with ZSTD (to save disk space)
if [ -z ${_compress_modules+x} ]; then
  _compress_modules=n
fi

# Compile ONLY used modules to VASTLY reduce the number of modules built
# and the build time.
#
# To keep track of which modules are needed for your specific system/hardware,
# give module_db script a try: https://aur.archlinux.org/packages/modprobed-db
# This PKGBUILD read the database kept if it exists
#
# More at this wiki page ---> https://wiki.archlinux.org/index.php/Modprobed-db
if [ -z ${_localmodcfg} ]; then
  _localmodcfg=n
fi

# Tweak kernel options prior to a build via nconfig
if [ -z ${_makenconfig} ]; then
  _makenconfig=n
fi

Personally I'm running now xanmod kernel compiled with this:

env _microarchitecture=98 use_tracers=n use_numa=n _localmodcfg=y _compress_modules=y makepkg -sic

Also, you can now create the file myconfig in your local repo to build this package with a custom config or use ${XDG_CONFIG_HOME}/linux-xanmod/myconfig. This file can be a full kernel config or be a script with several entries to add/remove options (you have several examples in PKGBUILD by using scripts/config):

Code involved:

  for _myconfig in "${SRCDEST}/myconfig" "${HOME}/.config/linux-xanmod/myconfig" "${XDG_CONFIG_HOME}/linux-xanmod/myconfig" ; do
    if [ -f "${_myconfig}" ] && [ "$(wc -l <"${_myconfig}")" -gt "0" ]; then
      if grep -q 'scripts/config' "${_myconfig}"; then
        # myconfig is a partial file. Executing as a script
        msg2 "Applying myconfig..."
        bash -x "${_myconfig}"
      else
        # myconfig is a full config file. Replacing default .config
        msg2 "Using user CUSTOM config..."
        cp -f "${_myconfig}" .config
      fi
      echo
      break
    fi
  done

Why is the default value for use_ns=n ? This breaks the evolution email client. evolution is not able to display emails with he following error:

bwrap: No permissions to creating new namespace, likely because the kernel does not allow non-privileged user namespaces. On e.g. debian this can be enabled with 'sysctl kernel.unprivileged_userns_clone=1'.

@Singularity indeed. Thanks for the comment.

Since we all compile the kernel here … one can boot without initramfs, if one compiles the modules necessary for accessing the hard drive into the kernel. With this PKGBUILD it's also quite practical, one can create the file "myconfig" next to the PKGBUILD with lines of the form "scripts/config --enable CONFIG_SATA_AHCI". I only needed that one additional module compiled in.

New package for XanMod + Cacule scheduler:

https://aur.archlinux.org/packages/linux-xanmod-cacule/

@xuanruiqi My apologies, it seems not stable yet and upstream decided to remove it for now. Instead I see that the cachy branch was updated. I'll revert the cacule advice for now until it becomes stable enough.

Edit: done 2ef6ccea265b

Where is linux-xanmod-cacule, though?

Thanks! af0a0f45aeae

Please see the warning here: https://wiki.archlinux.org/index.php/Kernel/Arch_Build_System#Modifying_the_PKGBUILD

@rayzorben let me ask to Alexander (upstream developer) about his plans with cachy... If this situation will be longer, I'll split it.