RPi4B buildworld buildkernel times for already installed system being -mcpu=cortex-a72 vs. -mcpu=cortex-a53 based

Sun Sep 27 18:07:57 UTC 2020

On 2020-Sep-20, at 18:40, Mark Millard <marklmi at yahoo.com> wrote:

> On 2020-Sep-20, at 18:32, Mark Millard <marklmi at yahoo.com> wrote:
> 
>> The following are from scratch buildworld buildkernel rebuilds
>> on a RPi4B (head -r363590 context).
>> 
>> ENVIRONMENT: -mcpu=cortex-a72 based world and kernel running already, RPi4B @ 2G Hz,
>> Restricted to 3 GiByte RAM, -j3:
>> 
>> World built in 37469 seconds, ncpu: 4, make -j3
>> Kernel(s)  GENERIC-NODBG built in 2474 seconds, ncpu: 4, make -j3
>> 
>> ENVIRONMENT: -mcpu=cortex-a53 based kernel running, RPi4B @ 2G Hz,
>> Restricted to 3 GiByte RAM, -j3:
>> 
>> World built in 44034 seconds, ncpu: 4, make -j3
>> Kernel(s)  GENERIC-NODBG built in 2895 seconds, ncpu: 4, make -j3
>> 
>> So a little under 11.1 hr total vs. a little over 13.0 hr total,
>> a somewhat over 50 min improvement.
> 
> "a somewhat over 1hr 50 min improvement" is what I should have
> managed to type.
> 
>> (A xhci patch finally allowed me to boot -mcpu=cortex-a72
>> based kernel builds on the RPi4B: The xhci event ring
>> initialization code was missing a usb_bus_mem_flush_all
>> call previously.)
>> 
>> 
>> Supporting details:
>> 
>> (e-mail based spacing changes expected below)
>> 
>> # diff -u ~/src.configs/src.conf.cortexA72-clang-bootstrap.aarch64-host ~/src.configs/src.conf.cortexA53-clang-bootstrap.aarch64-host
>> --- /root/src.configs/src.conf.cortexA72-clang-bootstrap.aarch64-host	2020-03-13 22:29:25.470155000 -0700
>> +++ /root/src.configs/src.conf.cortexA53-clang-bootstrap.aarch64-host	2020-03-13 22:29:25.469455000 -0700
>> @@ -49,9 +49,9 @@
>> # Use of the .clang 's here avoids
>> # interfering with other C<?>FLAGS
>> # usage, such as ?= usage.
>> -CFLAGS.clang+= -mcpu=cortex-a72
>> -CXXFLAGS.clang+= -mcpu=cortex-a72
>> -CPPFLAGS.clang+= -mcpu=cortex-a72
>> -ACFLAGS.arm64cpuid.S+=  -mcpu=cortex-a72+crypto
>> -ACFLAGS.aesv8-armx.S+=  -mcpu=cortex-a72+crypto
>> -ACFLAGS.ghashv8-armx.S+=        -mcpu=cortex-a72+crypto
>> +CFLAGS.clang+= -mcpu=cortex-a53
>> +CXXFLAGS.clang+= -mcpu=cortex-a53
>> +CPPFLAGS.clang+= -mcpu=cortex-a53
>> +ACFLAGS.arm64cpuid.S+=  -mcpu=cortex-a53+crypto
>> +ACFLAGS.aesv8-armx.S+=  -mcpu=cortex-a53+crypto
>> +ACFLAGS.ghashv8-armx.S+=        -mcpu=cortex-a53+crypto
>> 
>> 
>> The .amd64-host files are similar for doing cross builds.
>> 
>> I also use += in secure/lib/libcrypto/Makefile :
>> 
>> # svnlite diff /usr/src/secure/lib/libcrypto/Makefile
>> Index: /usr/src/secure/lib/libcrypto/Makefile
>> ===================================================================
>> --- /usr/src/secure/lib/libcrypto/Makefile	(revision 365919)
>> +++ /usr/src/secure/lib/libcrypto/Makefile	(working copy)
>> @@ -20,7 +20,7 @@
>> SRCS+=	o_str.c o_time.c threads_pthread.c uid.c
>> .if defined(ASM_aarch64)
>> SRCS+=	arm64cpuid.S armcap.c
>> -ACFLAGS.arm64cpuid.S=	-march=armv8-a+crypto
>> +ACFLAGS.arm64cpuid.S+=	-march=armv8-a+crypto
>> .elif defined(ASM_amd64)
>> SRCS+=	x86_64cpuid.S
>> .elif defined(ASM_arm)
>> @@ -35,7 +35,7 @@
>> SRCS+=	aes_cbc.c aes_cfb.c aes_ecb.c aes_ige.c aes_misc.c aes_ofb.c aes_wrap.c
>> .if defined(ASM_aarch64)
>> SRCS+=	aes_core.c aesv8-armx.S vpaes-armv8.S
>> -ACFLAGS.aesv8-armx.S=	-march=armv8-a+crypto
>> +ACFLAGS.aesv8-armx.S+=	-march=armv8-a+crypto
>> .elif defined(ASM_amd64)
>> SRCS+=	aes_core.c aesni-mb-x86_64.S aesni-sha1-x86_64.S aesni-sha256-x86_64.S
>> SRCS+=	aesni-x86_64.S vpaes-x86_64.S
>> @@ -242,7 +242,7 @@
>> SRCS+=	ofb128.c wrap128.c xts128.c
>> .if defined(ASM_aarch64)
>> SRCS+=	ghashv8-armx.S
>> -ACFLAGS.ghashv8-armx.S=	-march=armv8-a+crypto
>> +ACFLAGS.ghashv8-armx.S+=	-march=armv8-a+crypto
>> .elif defined(ASM_amd64)
>> SRCS+=	aesni-gcm-x86_64.S ghash-x86_64.S
>> .elif defined(ASM_arm)
>> 
>> The RPi4B is using:
>> 
>> over_voltage=6
>> arm_freq=2000
>> 
>> and was booted via uefi/ACPI.
>> 
>> I have not repeated the -j4 or other -jN comparisons that
>> I reported in the past. The -mcpu=cortex-a53 figures are
>> from the past.

The following new timing is based on head -r365932 rebuilding
itself where the 8 GiByte RPi4B config.txt ended with:

over_voltage=6
arm_freq=2000
sdram_freq_min=3200

and the boot was via u-boot, no RAM restriction. (The
sdram_freq_min assignment does not seem to do anything
for rpi4-uefi-devel v1.20 uefi/ACPI based booting.)
/etc/sysctl.conf has: dev.cpu.0.freq=2000 . No use of
powerd or other such.

ENVIRONMENT: -mcpu=cortex-a72 based world and kernel running already,
8 GiBYte RPi4B @ 2G Hz with sdram_freq_min=3200, u-boot style boot, -j3:

World built in 31852 seconds, ncpu: 4, make -j3
Kernel(s)  GENERIC-NODBG built in 2059 seconds, ncpu: 4, make -j3

So somewhat under 9.5 hr overall.

That means somewhat over 3.5 hours faster than a -mcpu=cortex-a53
based system without sdram_freq_min=3200 using 3 GiByte RAM
but still RPi4B @ 2G Hz (uefi/ACPI boot):

World built in 44034 seconds, ncpu: 4, make -j3
Kernel(s)  GENERIC-NODBG built in 2895 seconds, ncpu: 4, make -j3

(Same as reported in prior messages.)

But the prior -r362590 vs. the now -r363932 means there is more varying
than in my previous comparisons. For example, clang 10 vs. clang 11.

I'm probably going to run a -j4 build to see how it compares in
this context.

I've not run a default arm-freq/sdram_freq_min/dev.cpu.0.freq buildworld
buildkernel in a long time and so do not have reasonable comparison
figures relative to that type of context. I do not plan on such an
experiment.

I'll note that I run these tests with a monitor connected that sits
with a static login prompt display after booting. I do not not test
with X11 or other use that might significantly compete for more power.
The serial port console is usually used. I have used ssh sometimes in
the past.

~/src.configs/src.conf.cortexA72-clang-bootstrap.aarch64-host is still
unchanged:

# more ~/src.configs/src.conf.cortexA72-clang-bootstrap.aarch64-host 
TO_TYPE=aarch64
#
KERNCONF=GENERIC-NODBG
TARGET=arm64
.if ${.MAKE.LEVEL} == 0
TARGET_ARCH=${TO_TYPE}
.export TARGET_ARCH
.endif
#
#WITH_CROSS_COMPILER=
WITH_SYSTEM_COMPILER=
WITH_SYSTEM_LINKER=
#
WITH_LIBCPLUSPLUS=
#WITH_LLD_BOOTSTRAP=
WITHOUT_BINUTILS_BOOTSTRAP=
WITH_ELFTOOLCHAIN_BOOTSTRAP=
#Disables avoiding bootstrap: WITHOUT_LLVM_TARGET_ALL=
WITH_LLVM_TARGET_AARCH64=
WITH_LLVM_TARGET_ARM=
WITHOUT_LLVM_TARGET_MIPS=
WITHOUT_LLVM_TARGET_POWERPC=
WITHOUT_LLVM_TARGET_RISCV=
WITHOUT_LLVM_TARGET_X86=
#WITH_CLANG_BOOTSTRAP=
WITH_CLANG=
WITH_CLANG_IS_CC=
WITH_CLANG_FULL=
WITH_CLANG_EXTRAS=
WITH_LLD=
WITH_LLD_IS_LD=
WITHOUT_BINUTILS=
WITH_LLDB=
#
WITH_BOOT=
WITHOUT_LIB32=
#
#
NO_WERROR=
#WERROR=
MALLOC_PRODUCTION=
#
# Avoid stripping but do not control host -g status as well:
DEBUG_FLAGS+=
#
WITH_REPRODUCIBLE_BUILD=
WITH_DEBUG_FILES=
#
# Use of the .clang 's here avoids
# interfering with other C<?>FLAGS
# usage, such as ?= usage.
CFLAGS.clang+= -mcpu=cortex-a72
CXXFLAGS.clang+= -mcpu=cortex-a72
CPPFLAGS.clang+= -mcpu=cortex-a72
ACFLAGS.arm64cpuid.S+=  -mcpu=cortex-a72+crypto
ACFLAGS.aesv8-armx.S+=  -mcpu=cortex-a72+crypto
ACFLAGS.ghashv8-armx.S+=        -mcpu=cortex-a72+crypto

===
Mark Millard
marklmi at yahoo.com
( dsl-only.net went
away in early 2018-Mar)