将llvm use flag从gentoo全局标记中移除,加快编译构建过程
很长时间没有升级Gentoo Linux了, 手痒执行了一次全系统更新, 发现比以前的升级编译的时间长了非常多.
看了下log, 花时间最多的地方在gcc/mesa/llvm这三个包, 顺带研究了下gcc/llvm的关系,又使用equery 检查了下llvm包的依赖关系, 整个系统只有mesa一个包直接依赖llvm,对于个人用户, 建议还是果断将 -llvm use 标记添加到/etc/portage/make.conf, 减少升级编译的时间.除非你的工作确实需要llvm.以下是我优化后的mesa包的use标记列表:
下面是我的/etc/portage/make.conf中的USE变量配置的内容,我比较喜欢mate的简单,所以qt/kde等等都被移除了.
USE="${USE} systemd -samba ipv6 -cups -qt4 -ldap -gnome -kde jpeg jpeg2k tk -llvm"equery u media-libs/mesa-18.2.8
U I
+ + abi_x86_32 : 32-bit (x86) libraries
- - bindist : Disable patent-encumbered ARB_texture_float, EXT_texture_shared_exponent, and EXT_packed_float extensions.
+ + classic : Build drivers based on the classic architecture.
- - d3d9 : Enable Direct 3D9 API through Nine state tracker. Can be used together with patched wine.
- - debug : Enable extra debug codepaths, like asserts and extra output. If you want to get meaningful backtraces see https://wiki.gentoo.org/wiki/Project:Quality_Assurance/Backtraces
+ + dri3 : Enable DRI3 support.
+ + egl : Enable EGL support.
+ + gallium : Build drivers based on Gallium3D, the new architecture for 3D graphics drivers.
+ + gbm : Enable the Graphics Buffer Manager for EGL on KMS.
- - gles1 : Enable GLESv1 support.
- - gles2 : Enable GLESv2 support.
- - llvm : Enable LLVM backend for Gallium3D.
+ + nptl : Enable support for Native POSIX Threads Library, the new threading module (requires linux-2.6 or better usually)
- - opencl : Enable the Clover Gallium OpenCL state tracker.
- - openmax : Enable OpenMAX video decode/encode acceleration for Gallium3D.
- - osmesa : Build the Mesa library for off-screen rendering.
- - pax_kernel : Enable if the user plans to run the package under a pax enabled hardened kernel
- - pic : disable optimized assembly code that is not PIC friendly
- - vaapi : Enable Video Acceleration API for hardware decoding
- - valgrind : Compile in valgrind memory hints
- - vdpau : Enable the VDPAU acceleration interface for the Gallium3D Video Layer.
+ + video_cards_i915 : VIDEO_CARDS setting to build driver for Intel i915 video cards
+ + video_cards_i965 : VIDEO_CARDS setting to build driver for Intel i965 video cards
- - video_cards_imx : VIDEO_CARDS setting to build driver for Freescale i.MX video cards
+ + video_cards_intel : VIDEO_CARDS setting to build driver for Intel video cards
- - video_cards_nouveau : VIDEO_CARDS setting to build reverse-engineered driver for nvidia cards
- - video_cards_r100 : VIDEO_CARDS setting to build only r100 based chips code for radeon
- - video_cards_r200 : VIDEO_CARDS setting to build only r200 based chips code for radeon
- - video_cards_r300 : VIDEO_CARDS setting to build only r300, r400 and r500 based chips code for radeon
- - video_cards_r600 : VIDEO_CARDS setting to build only r600, r700, Evergreen and Northern Islands based chips code for radeon
- - video_cards_radeon : VIDEO_CARDS setting to build driver for ATI radeon video cards
- - video_cards_radeonsi : VIDEO_CARDS setting to build only Southern Islands based chips code for radeon
- - video_cards_vmware : VIDEO_CARDS setting to build driver for vmware video cards
- - vulkan : Enable Vulkan drivers
- - wayland : Enable support for dev-libs/wayland
- - xa : Enable the XA (X Acceleration) API for Gallium3D.
+ + xvmc : Enable the XvMC acceleration interface for the Gallium3D Video Layer.参考链接
