CVSROOT: /cvs
Module name: src
Changes by: [email protected] 2026/03/31 10:46:22
Modified files:
sys/sys : sched.h sysctl.h
sys/kern : kern_sched.c kern_sysctl.c
sys/arch/amd64/amd64: identcpu.c machdep.c
sys/arch/amd64/include: cpu.h
lib/libc/sys : sysctl.2
Log message:
Some new intel machines have a new 3rd tier of cpus called LP-E which are
E-core (Atom) without L3 cache. These cpus are Lethargic, and it sucks
when processes migrate to them.
This introduces sysctl hw.blockcpu= which takes a sequence of 4 letters.
S (for SMT), P (regular performance cpu), E (efficient cpu) generally
80% to 50% as fast), and L (lethargic cpu) which are even slower.
By setting this, you can select cpus to kick out of the scheduler. The
default is SL.
The hw.smt sysctl remains for now but we will eventually delete it.
hw.smt changes and follows hw.blockcpu=S.
ok kettenis mlarkin
