[U-Boot] [PATCH 0/2] Add ccache support

These two patches make it easy to use ccache with U-Boot to speed up iterative builds.
The results of building SoC MXS without ccache: real 1m29.286s user 7m1.972s sys 0m46.668s
The results of building SoC MXS with ccache for the first time: real 1m37.551s user 7m23.632s sys 0m59.332s
The results of building SoC MXS with ccache again: real 0m41.968s user 1m9.912s sys 0m20.028s
The speedup is significant.
Marek Vasut (2): common: Add CCACHE variable to allow use of ccache common: Use separate dirs for each board for ccache
MAKEALL | 7 +++++++ config.mk | 8 +++++--- 2 files changed, 12 insertions(+), 3 deletions(-)

Prefix HOSTCC and CC with CCACHE variable to allow easy use of ccache. In case the user wants to use ccache, exporting CCACHE=ccache will do the trick. It is of course possible to either make the cross-compiler name into a shellscript which invokes the ccache and the compiler, but setting this variable makes use of ccache easier and more convenient.
Using ccache becomes convenient when using MAKEALL for large build tests, where the speedup after building the cache for the first time is about 4-6 times.
Signed-off-by: Marek Vasut marex@denx.de Cc: Tom Rini trini@ti.com --- config.mk | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/config.mk b/config.mk index 1fd109f..d59ded2 100644 --- a/config.mk +++ b/config.mk @@ -98,6 +98,8 @@ else HOSTCC = gcc endif
+HOSTCC := $(CCACHE) $(HOSTCC) + ifeq ($(HOSTOS),cygwin) HOSTCFLAGS += -ansi endif @@ -140,13 +142,13 @@ binutils-version = $(shell $(SHELL) $(SRCTREE)/tools/binutils-version.sh $(AS)) # # Include the make variables (CC, etc...) # -AS = $(CROSS_COMPILE)as +AS = $(CCACHE) $(CROSS_COMPILE)as
# Always use GNU ld LD = $(shell if $(CROSS_COMPILE)ld.bfd -v > /dev/null 2>&1; \ then echo "$(CROSS_COMPILE)ld.bfd"; else echo "$(CROSS_COMPILE)ld"; fi;)
-CC = $(CROSS_COMPILE)gcc +CC = $(CCACHE) $(CROSS_COMPILE)gcc CPP = $(CC) -E AR = $(CROSS_COMPILE)ar NM = $(CROSS_COMPILE)nm @@ -320,7 +322,7 @@ endif
#########################################################################
-export HOSTCC HOSTCFLAGS HOSTLDFLAGS PEDCFLAGS HOSTSTRIP CROSS_COMPILE \ +export HOSTCC HOSTCFLAGS HOSTLDFLAGS PEDCFLAGS HOSTSTRIP CROSS_COMPILE CCACHE \ AS LD CC CPP AR NM STRIP OBJCOPY OBJDUMP MAKE export CONFIG_SYS_TEXT_BASE PLATFORM_CPPFLAGS PLATFORM_RELFLAGS CPPFLAGS CFLAGS AFLAGS

Dear Marek Vasut,
In message 1369070715-9585-2-git-send-email-marex@denx.de you wrote:
Prefix HOSTCC and CC with CCACHE variable to allow easy use of ccache. In case the user wants to use ccache, exporting CCACHE=ccache will do the trick. It is of course possible to either make the cross-compiler name into a shellscript which invokes the ccache and the compiler, but setting this variable makes use of ccache easier and more convenient.
...
-AS = $(CROSS_COMPILE)as +AS = $(CCACHE) $(CROSS_COMPILE)as
# Always use GNU ld LD = $(shell if $(CROSS_COMPILE)ld.bfd -v > /dev/null 2>&1; \ then echo "$(CROSS_COMPILE)ld.bfd"; else echo "$(CROSS_COMPILE)ld"; fi;)
-CC = $(CROSS_COMPILE)gcc +CC = $(CCACHE) $(CROSS_COMPILE)gcc CPP = $(CC) -E
Why not for CPP ?
Best regards,
Wolfgang Denk

Dear Wolfgang Denk,
Dear Marek Vasut,
In message 1369070715-9585-2-git-send-email-marex@denx.de you wrote:
Prefix HOSTCC and CC with CCACHE variable to allow easy use of ccache. In case the user wants to use ccache, exporting CCACHE=ccache will do the trick. It is of course possible to either make the cross-compiler name into a shellscript which invokes the ccache and the compiler, but setting this variable makes use of ccache easier and more convenient.
...
-AS = $(CROSS_COMPILE)as +AS = $(CCACHE) $(CROSS_COMPILE)as
# Always use GNU ld LD = $(shell if $(CROSS_COMPILE)ld.bfd -v > /dev/null 2>&1; \
then echo "$(CROSS_COMPILE)ld.bfd"; else echo
"$(CROSS_COMPILE)ld";
fi;)
-CC = $(CROSS_COMPILE)gcc +CC = $(CCACHE) $(CROSS_COMPILE)gcc
CPP = $(CC) -E
Why not for CPP ?
CPP is invoked via $(CC) -E and CCACHE is set for CC right above, so that'd call ccache twice.
Best regards, Marek Vasut

On 05/20/2013 10:25 AM, Marek Vasut wrote:
Prefix HOSTCC and CC with CCACHE variable to allow easy use of ccache. In case the user wants to use ccache, exporting CCACHE=ccache will do the trick. It is of course possible to either make the cross-compiler name into a shellscript which invokes the ccache and the compiler, but setting this variable makes use of ccache easier and more convenient.
Using ccache becomes convenient when using MAKEALL for large build tests, where the speedup after building the cache for the first time is about 4-6 times.
Signed-off-by: Marek Vasut marex@denx.de Cc: Tom Rini trini@ti.com
config.mk | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/config.mk b/config.mk index 1fd109f..d59ded2 100644 --- a/config.mk +++ b/config.mk @@ -98,6 +98,8 @@ else HOSTCC = gcc endif
+HOSTCC := $(CCACHE) $(HOSTCC)
ifeq ($(HOSTOS),cygwin) HOSTCFLAGS += -ansi endif @@ -140,13 +142,13 @@ binutils-version = $(shell $(SHELL) $(SRCTREE)/tools/binutils-version.sh $(AS)) # # Include the make variables (CC, etc...) # -AS = $(CROSS_COMPILE)as +AS = $(CCACHE) $(CROSS_COMPILE)as
# Always use GNU ld LD = $(shell if $(CROSS_COMPILE)ld.bfd -v > /dev/null 2>&1; \ then echo "$(CROSS_COMPILE)ld.bfd"; else echo "$(CROSS_COMPILE)ld"; fi;)
-CC = $(CROSS_COMPILE)gcc +CC = $(CCACHE) $(CROSS_COMPILE)gcc CPP = $(CC) -E AR = $(CROSS_COMPILE)ar NM = $(CROSS_COMPILE)nm @@ -320,7 +322,7 @@ endif
#########################################################################
-export HOSTCC HOSTCFLAGS HOSTLDFLAGS PEDCFLAGS HOSTSTRIP CROSS_COMPILE \ +export HOSTCC HOSTCFLAGS HOSTLDFLAGS PEDCFLAGS HOSTSTRIP CROSS_COMPILE CCACHE \ AS LD CC CPP AR NM STRIP OBJCOPY OBJDUMP MAKE export CONFIG_SYS_TEXT_BASE PLATFORM_CPPFLAGS PLATFORM_RELFLAGS CPPFLAGS CFLAGS AFLAGS
Where did this patch go? I found it useful.
York

Dear York Sun,
On 05/20/2013 10:25 AM, Marek Vasut wrote:
Prefix HOSTCC and CC with CCACHE variable to allow easy use of ccache. In case the user wants to use ccache, exporting CCACHE=ccache will do the trick. It is of course possible to either make the cross-compiler name into a shellscript which invokes the ccache and the compiler, but setting this variable makes use of ccache easier and more convenient.
Using ccache becomes convenient when using MAKEALL for large build tests, where the speedup after building the cache for the first time is about 4-6 times.
Signed-off-by: Marek Vasut marex@denx.de Cc: Tom Rini trini@ti.com
config.mk | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/config.mk b/config.mk index 1fd109f..d59ded2 100644 --- a/config.mk +++ b/config.mk @@ -98,6 +98,8 @@ else
HOSTCC = gcc endif
+HOSTCC := $(CCACHE) $(HOSTCC)
ifeq ($(HOSTOS),cygwin) HOSTCFLAGS += -ansi endif
@@ -140,13 +142,13 @@ binutils-version = $(shell $(SHELL) $(SRCTREE)/tools/binutils-version.sh $(AS))
# # Include the make variables (CC, etc...) #
-AS = $(CROSS_COMPILE)as +AS = $(CCACHE) $(CROSS_COMPILE)as
# Always use GNU ld LD = $(shell if $(CROSS_COMPILE)ld.bfd -v > /dev/null 2>&1; \
then echo "$(CROSS_COMPILE)ld.bfd"; else echo
"$(CROSS_COMPILE)ld";
fi;)
-CC = $(CROSS_COMPILE)gcc +CC = $(CCACHE) $(CROSS_COMPILE)gcc
CPP = $(CC) -E AR = $(CROSS_COMPILE)ar NM = $(CROSS_COMPILE)nm
@@ -320,7 +322,7 @@ endif
######################################################################## #
-export HOSTCC HOSTCFLAGS HOSTLDFLAGS PEDCFLAGS HOSTSTRIP CROSS_COMPILE
\
+export HOSTCC HOSTCFLAGS HOSTLDFLAGS PEDCFLAGS HOSTSTRIP CROSS_COMPILE CCACHE \
AS LD CC CPP AR NM STRIP OBJCOPY OBJDUMP MAKE
export CONFIG_SYS_TEXT_BASE PLATFORM_CPPFLAGS PLATFORM_RELFLAGS
CPPFLAGS
CFLAGS AFLAGS
Where did this patch go? I found it useful.
It needs additional fixes, try running with MAKEALL and you will see the problem -- the problem is you would need separate ccache for each MAKEALL thread.
Best regards, Marek Vasut

On Aug 21, 2013, at 7:51 PM, Marek Vasut wrote:
Dear York Sun,
On 05/20/2013 10:25 AM, Marek Vasut wrote:
Prefix HOSTCC and CC with CCACHE variable to allow easy use of ccache. In case the user wants to use ccache, exporting CCACHE=ccache will do the trick. It is of course possible to either make the cross-compiler name into a shellscript which invokes the ccache and the compiler, but setting this variable makes use of ccache easier and more convenient.
Using ccache becomes convenient when using MAKEALL for large build tests, where the speedup after building the cache for the first time is about 4-6 times.
Signed-off-by: Marek Vasut marex@denx.de Cc: Tom Rini trini@ti.com
config.mk | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/config.mk b/config.mk index 1fd109f..d59ded2 100644 --- a/config.mk +++ b/config.mk @@ -98,6 +98,8 @@ else
HOSTCC = gcc endif
+HOSTCC := $(CCACHE) $(HOSTCC)
ifeq ($(HOSTOS),cygwin) HOSTCFLAGS += -ansi endif
@@ -140,13 +142,13 @@ binutils-version = $(shell $(SHELL) $(SRCTREE)/tools/binutils-version.sh $(AS))
# # Include the make variables (CC, etc...) #
-AS = $(CROSS_COMPILE)as +AS = $(CCACHE) $(CROSS_COMPILE)as
# Always use GNU ld LD = $(shell if $(CROSS_COMPILE)ld.bfd -v > /dev/null 2>&1; \
then echo "$(CROSS_COMPILE)ld.bfd"; else echo
"$(CROSS_COMPILE)ld";
fi;)
-CC = $(CROSS_COMPILE)gcc +CC = $(CCACHE) $(CROSS_COMPILE)gcc
CPP = $(CC) -E AR = $(CROSS_COMPILE)ar NM = $(CROSS_COMPILE)nm
@@ -320,7 +322,7 @@ endif
######################################################################## #
-export HOSTCC HOSTCFLAGS HOSTLDFLAGS PEDCFLAGS HOSTSTRIP CROSS_COMPILE
\
+export HOSTCC HOSTCFLAGS HOSTLDFLAGS PEDCFLAGS HOSTSTRIP CROSS_COMPILE CCACHE \
AS LD CC CPP AR NM STRIP OBJCOPY OBJDUMP MAKE
export CONFIG_SYS_TEXT_BASE PLATFORM_CPPFLAGS PLATFORM_RELFLAGS
CPPFLAGS
CFLAGS AFLAGS
Where did this patch go? I found it useful.
It needs additional fixes, try running with MAKEALL and you will see the problem -- the problem is you would need separate ccache for each MAKEALL thread.
I didn't use this patch but I modified config.mk as this patch did. MAKEALL works fine for "-a powerpc". It cuts my compiling time more than half for 660+ boards.
York

Dear sun york-R58495,
On Aug 21, 2013, at 7:51 PM, Marek Vasut wrote:
Dear York Sun,
On 05/20/2013 10:25 AM, Marek Vasut wrote:
Prefix HOSTCC and CC with CCACHE variable to allow easy use of ccache. In case the user wants to use ccache, exporting CCACHE=ccache will do the trick. It is of course possible to either make the cross-compiler name into a shellscript which invokes the ccache and the compiler, but setting this variable makes use of ccache easier and more convenient.
Using ccache becomes convenient when using MAKEALL for large build tests, where the speedup after building the cache for the first time is about 4-6 times.
Signed-off-by: Marek Vasut marex@denx.de Cc: Tom Rini trini@ti.com
config.mk | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/config.mk b/config.mk index 1fd109f..d59ded2 100644 --- a/config.mk +++ b/config.mk @@ -98,6 +98,8 @@ else
HOSTCC = gcc endif
+HOSTCC := $(CCACHE) $(HOSTCC)
ifeq ($(HOSTOS),cygwin) HOSTCFLAGS += -ansi endif
@@ -140,13 +142,13 @@ binutils-version = $(shell $(SHELL) $(SRCTREE)/tools/binutils-version.sh $(AS))
# # Include the make variables (CC, etc...) #
-AS = $(CROSS_COMPILE)as +AS = $(CCACHE) $(CROSS_COMPILE)as
# Always use GNU ld LD = $(shell if $(CROSS_COMPILE)ld.bfd -v > /dev/null 2>&1; \
then echo "$(CROSS_COMPILE)ld.bfd"; else echo
"$(CROSS_COMPILE)ld";
fi;)
-CC = $(CROSS_COMPILE)gcc +CC = $(CCACHE) $(CROSS_COMPILE)gcc
CPP = $(CC) -E AR = $(CROSS_COMPILE)ar NM = $(CROSS_COMPILE)nm
@@ -320,7 +322,7 @@ endif
####################################################################### # #
-export HOSTCC HOSTCFLAGS HOSTLDFLAGS PEDCFLAGS HOSTSTRIP CROSS_COMPILE
\
+export HOSTCC HOSTCFLAGS HOSTLDFLAGS PEDCFLAGS HOSTSTRIP CROSS_COMPILE CCACHE \
AS LD CC CPP AR NM STRIP OBJCOPY OBJDUMP MAKE
export CONFIG_SYS_TEXT_BASE PLATFORM_CPPFLAGS PLATFORM_RELFLAGS
CPPFLAGS
CFLAGS AFLAGS
Where did this patch go? I found it useful.
It needs additional fixes, try running with MAKEALL and you will see the problem -- the problem is you would need separate ccache for each MAKEALL thread.
I didn't use this patch but I modified config.mk as this patch did. MAKEALL works fine for "-a powerpc". It cuts my compiling time more than half for 660+ boards.
That is still poor, it should be much faster. If you use separate ccache for each board, then it will be _much_ more performant.
The problem is that when rebuilding all of those 680 configurations, the cached files get replaced by ones based on different board config all the time => you need to rebuild them => you loose performance.
Best regards, Marek Vasut

On Aug 21, 2013, at 10:02 PM, Marek Vasut wrote:
Dear sun york-R58495,
On Aug 21, 2013, at 7:51 PM, Marek Vasut wrote:
Dear York Sun,
On 05/20/2013 10:25 AM, Marek Vasut wrote:
Prefix HOSTCC and CC with CCACHE variable to allow easy use of ccache. In case the user wants to use ccache, exporting CCACHE=ccache will do the trick. It is of course possible to either make the cross-compiler name into a shellscript which invokes the ccache and the compiler, but setting this variable makes use of ccache easier and more convenient.
Using ccache becomes convenient when using MAKEALL for large build tests, where the speedup after building the cache for the first time is about 4-6 times.
Signed-off-by: Marek Vasut marex@denx.de Cc: Tom Rini trini@ti.com
config.mk | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/config.mk b/config.mk index 1fd109f..d59ded2 100644 --- a/config.mk +++ b/config.mk @@ -98,6 +98,8 @@ else
HOSTCC = gcc endif
+HOSTCC := $(CCACHE) $(HOSTCC)
ifeq ($(HOSTOS),cygwin) HOSTCFLAGS += -ansi endif
@@ -140,13 +142,13 @@ binutils-version = $(shell $(SHELL) $(SRCTREE)/tools/binutils-version.sh $(AS))
# # Include the make variables (CC, etc...) #
-AS = $(CROSS_COMPILE)as +AS = $(CCACHE) $(CROSS_COMPILE)as
# Always use GNU ld LD = $(shell if $(CROSS_COMPILE)ld.bfd -v > /dev/null 2>&1; \
then echo "$(CROSS_COMPILE)ld.bfd"; else echo
"$(CROSS_COMPILE)ld";
fi;)
-CC = $(CROSS_COMPILE)gcc +CC = $(CCACHE) $(CROSS_COMPILE)gcc
CPP = $(CC) -E AR = $(CROSS_COMPILE)ar NM = $(CROSS_COMPILE)nm
@@ -320,7 +322,7 @@ endif
####################################################################### # #
-export HOSTCC HOSTCFLAGS HOSTLDFLAGS PEDCFLAGS HOSTSTRIP CROSS_COMPILE
\
+export HOSTCC HOSTCFLAGS HOSTLDFLAGS PEDCFLAGS HOSTSTRIP CROSS_COMPILE CCACHE \
AS LD CC CPP AR NM STRIP OBJCOPY OBJDUMP MAKE
export CONFIG_SYS_TEXT_BASE PLATFORM_CPPFLAGS PLATFORM_RELFLAGS
CPPFLAGS
CFLAGS AFLAGS
Where did this patch go? I found it useful.
It needs additional fixes, try running with MAKEALL and you will see the problem -- the problem is you would need separate ccache for each MAKEALL thread.
I didn't use this patch but I modified config.mk as this patch did. MAKEALL works fine for "-a powerpc". It cuts my compiling time more than half for 660+ boards.
That is still poor, it should be much faster. If you use separate ccache for each board, then it will be _much_ more performant.
The problem is that when rebuilding all of those 680 configurations, the cached files get replaced by ones based on different board config all the time => you need to rebuild them => you loose performance.
I kind of get it. I have to increase my ccache size a lot (more than 2GB) to get consistent cache hit. I thought that was because I was using out-of-tree build when setting BUILD_NBUILDS. For the first time I run MAKEALL with ccache, it was completely miss. I mean zero hit. It would be nice to be able hit the cache. I was read the ccache document to understand how the path is involved when calculating the hash. How do you plan to make it work?
York

On Aug 21, 2013, at 10:45 PM, sun york-R58495 wrote:
On Aug 21, 2013, at 10:02 PM, Marek Vasut wrote:
Dear sun york-R58495,
On Aug 21, 2013, at 7:51 PM, Marek Vasut wrote:
Dear York Sun,
On 05/20/2013 10:25 AM, Marek Vasut wrote:
Prefix HOSTCC and CC with CCACHE variable to allow easy use of ccache. In case the user wants to use ccache, exporting CCACHE=ccache will do the trick. It is of course possible to either make the cross-compiler name into a shellscript which invokes the ccache and the compiler, but setting this variable makes use of ccache easier and more convenient.
Using ccache becomes convenient when using MAKEALL for large build tests, where the speedup after building the cache for the first time is about 4-6 times.
Signed-off-by: Marek Vasut marex@denx.de Cc: Tom Rini trini@ti.com
config.mk | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/config.mk b/config.mk index 1fd109f..d59ded2 100644 --- a/config.mk +++ b/config.mk @@ -98,6 +98,8 @@ else
HOSTCC = gcc endif
+HOSTCC := $(CCACHE) $(HOSTCC)
ifeq ($(HOSTOS),cygwin) HOSTCFLAGS += -ansi endif
@@ -140,13 +142,13 @@ binutils-version = $(shell $(SHELL) $(SRCTREE)/tools/binutils-version.sh $(AS))
# # Include the make variables (CC, etc...) #
-AS = $(CROSS_COMPILE)as +AS = $(CCACHE) $(CROSS_COMPILE)as
# Always use GNU ld LD = $(shell if $(CROSS_COMPILE)ld.bfd -v > /dev/null 2>&1; \
then echo "$(CROSS_COMPILE)ld.bfd"; else echo
"$(CROSS_COMPILE)ld";
fi;)
-CC = $(CROSS_COMPILE)gcc +CC = $(CCACHE) $(CROSS_COMPILE)gcc
CPP = $(CC) -E AR = $(CROSS_COMPILE)ar NM = $(CROSS_COMPILE)nm
@@ -320,7 +322,7 @@ endif
####################################################################### # #
-export HOSTCC HOSTCFLAGS HOSTLDFLAGS PEDCFLAGS HOSTSTRIP CROSS_COMPILE
\
+export HOSTCC HOSTCFLAGS HOSTLDFLAGS PEDCFLAGS HOSTSTRIP CROSS_COMPILE CCACHE \
AS LD CC CPP AR NM STRIP OBJCOPY OBJDUMP MAKE
export CONFIG_SYS_TEXT_BASE PLATFORM_CPPFLAGS PLATFORM_RELFLAGS
CPPFLAGS
CFLAGS AFLAGS
Where did this patch go? I found it useful.
It needs additional fixes, try running with MAKEALL and you will see the problem -- the problem is you would need separate ccache for each MAKEALL thread.
I didn't use this patch but I modified config.mk as this patch did. MAKEALL works fine for "-a powerpc". It cuts my compiling time more than half for 660+ boards.
That is still poor, it should be much faster. If you use separate ccache for each board, then it will be _much_ more performant.
The problem is that when rebuilding all of those 680 configurations, the cached files get replaced by ones based on different board config all the time => you need to rebuild them => you loose performance.
I kind of get it. I have to increase my ccache size a lot (more than 2GB) to get consistent cache hit. I thought that was because I was using out-of-tree build when setting BUILD_NBUILDS. For the first time I run MAKEALL with ccache, it was completely miss. I mean zero hit. It would be nice to be able hit the cache. I was read the ccache document to understand how the path is involved when calculating the hash. How do you plan to make it work?
I forgot to mention, if the ccache size is at default (1GB), I don't see any performance improvement by using ccache. I think that's what you meant the cached files get replaced. I don't understand what you mean to use separated ccache for each board. Would it be equivalent to have a big cache? I was compiling with and without BUILD_NBUILDS, and my cache size is more than 3GB now. I could see the improvement by 2x~3x faster, but not more.
York

Dear sun york-R58495,
On Aug 21, 2013, at 10:45 PM, sun york-R58495 wrote:
On Aug 21, 2013, at 10:02 PM, Marek Vasut wrote:
Dear sun york-R58495,
On Aug 21, 2013, at 7:51 PM, Marek Vasut wrote:
Dear York Sun,
On 05/20/2013 10:25 AM, Marek Vasut wrote: > Prefix HOSTCC and CC with CCACHE variable to allow easy use of > ccache. In case the user wants to use ccache, exporting > CCACHE=ccache will do the trick. It is of course possible to either > make the cross-compiler name into a shellscript which invokes the > ccache and the compiler, but setting this variable makes use of > ccache easier and more convenient. > > Using ccache becomes convenient when using MAKEALL for large build > tests, where the speedup after building the cache for the first time > is about 4-6 times. > > Signed-off-by: Marek Vasut marex@denx.de > Cc: Tom Rini trini@ti.com > > --- > config.mk | 8 +++++--- > > 1 file changed, 5 insertions(+), 3 deletions(-) > > diff --git a/config.mk b/config.mk > index 1fd109f..d59ded2 100644 > --- a/config.mk > +++ b/config.mk > @@ -98,6 +98,8 @@ else > > HOSTCC = gcc > endif > > +HOSTCC := $(CCACHE) $(HOSTCC) > + > > ifeq ($(HOSTOS),cygwin) > HOSTCFLAGS += -ansi > endif > > @@ -140,13 +142,13 @@ binutils-version = $(shell $(SHELL) > $(SRCTREE)/tools/binutils-version.sh $(AS)) > > # > # Include the make variables (CC, etc...) > # > > -AS = $(CROSS_COMPILE)as > +AS = $(CCACHE) $(CROSS_COMPILE)as > > # Always use GNU ld > LD = $(shell if $(CROSS_COMPILE)ld.bfd -v > /dev/null 2>&1; \ > > then echo "$(CROSS_COMPILE)ld.bfd"; else echo
"$(CROSS_COMPILE)ld";
> fi;) > > -CC = $(CROSS_COMPILE)gcc > +CC = $(CCACHE) $(CROSS_COMPILE)gcc > > CPP = $(CC) -E > AR = $(CROSS_COMPILE)ar > NM = $(CROSS_COMPILE)nm > > @@ -320,7 +322,7 @@ endif > > #################################################################### > ### # # > > -export HOSTCC HOSTCFLAGS HOSTLDFLAGS PEDCFLAGS HOSTSTRIP > CROSS_COMPILE
\
> +export HOSTCC HOSTCFLAGS HOSTLDFLAGS PEDCFLAGS HOSTSTRIP > CROSS_COMPILE CCACHE \ > > AS LD CC CPP AR NM STRIP OBJCOPY OBJDUMP MAKE > > export CONFIG_SYS_TEXT_BASE PLATFORM_CPPFLAGS PLATFORM_RELFLAGS
CPPFLAGS
> CFLAGS AFLAGS
Where did this patch go? I found it useful.
It needs additional fixes, try running with MAKEALL and you will see the problem -- the problem is you would need separate ccache for each MAKEALL thread.
I didn't use this patch but I modified config.mk as this patch did. MAKEALL works fine for "-a powerpc". It cuts my compiling time more than half for 660+ boards.
That is still poor, it should be much faster. If you use separate ccache for each board, then it will be _much_ more performant.
The problem is that when rebuilding all of those 680 configurations, the cached files get replaced by ones based on different board config all the time => you need to rebuild them => you loose performance.
I kind of get it. I have to increase my ccache size a lot (more than 2GB) to get consistent cache hit. I thought that was because I was using out-of-tree build when setting BUILD_NBUILDS. For the first time I run MAKEALL with ccache, it was completely miss. I mean zero hit. It would be nice to be able hit the cache. I was read the ccache document to understand how the path is involved when calculating the hash. How do you plan to make it work?
I forgot to mention, if the ccache size is at default (1GB), I don't see any performance improvement by using ccache. I think that's what you meant the cached files get replaced. I don't understand what you mean to use separated ccache for each board. Would it be equivalent to have a big cache? I was compiling with and without BUILD_NBUILDS, and my cache size is more than 3GB now. I could see the improvement by 2x~3x faster, but not more.
There is an env variable to configure separate ccache cache dir , so just by setting that. But then , when each build ends, you would need to clean it up somehow. It was mentioned in the discussion with the patch. You can try working on this some more and post a patch, then we can talk about further forging of this.
Best regards, Marek Vasut

On 08/22/2013 12:36 PM, Marek Vasut wrote:
There is an env variable to configure separate ccache cache dir , so just by setting that. But then , when each build ends, you would need to clean it up somehow. It was mentioned in the discussion with the patch. You can try working on this some more and post a patch, then we can talk about further forging of this.
I fixed the 2nd patch and I am running MAKEALL with individual board folder for ccache. The compiling time for the first run on my laptop is 56 minutes. The 2nd run is 23 minutes. About the same improvement if using a big unified cache for all boards. By the way, each board cache is about 7~8MB.
You set my expectation high. I was hoping to get 10x or more improvement.
York

Dear York Sun,
On 08/22/2013 12:36 PM, Marek Vasut wrote:
There is an env variable to configure separate ccache cache dir , so just by setting that. But then , when each build ends, you would need to clean it up somehow. It was mentioned in the discussion with the patch. You can try working on this some more and post a patch, then we can talk about further forging of this.
I fixed the 2nd patch and I am running MAKEALL with individual board folder for ccache. The compiling time for the first run on my laptop is 56 minutes. The 2nd run is 23 minutes. About the same improvement if using a big unified cache for all boards. By the way, each board cache is about 7~8MB.
You set my expectation high. I was hoping to get 10x or more improvement.
It should be more, try checking if there is no bottleneck.
Best regards, Marek Vasut

On 08/22/2013 08:05 PM, Marek Vasut wrote:
Dear York Sun,
On 08/22/2013 12:36 PM, Marek Vasut wrote:
There is an env variable to configure separate ccache cache dir , so just by setting that. But then , when each build ends, you would need to clean it up somehow. It was mentioned in the discussion with the patch. You can try working on this some more and post a patch, then we can talk about further forging of this.
I fixed the 2nd patch and I am running MAKEALL with individual board folder for ccache. The compiling time for the first run on my laptop is 56 minutes. The 2nd run is 23 minutes. About the same improvement if using a big unified cache for all boards. By the way, each board cache is about 7~8MB.
You set my expectation high. I was hoping to get 10x or more improvement.
It should be more, try checking if there is no bottleneck.
I can send you the patch. Will you be able to test?
York

When using ccache in MAKEALL, use separate directory for the cache for each board. This way we can avoid rewriting the same files by building other boards.
Signed-off-by: Marek Vasut marex@denx.de Cc: Tom Rini trini@ti.com --- MAKEALL | 7 +++++++ 1 file changed, 7 insertions(+)
diff --git a/MAKEALL b/MAKEALL index 2737eab..b945007 100755 --- a/MAKEALL +++ b/MAKEALL @@ -673,6 +673,13 @@ build_target() { MAKE=make fi
+ # Use per-board CCACHE directory + if [ "x${CCACHE}" != "x" ] ; then + export CCACHE_DIR="`${CCACHE} -s | grep "^cache directory" | \ + tr -s " " | cut -d " " -f 3`/u-boot/${target}" ; + mkdir -p "${CCACHE_DIR}" + fi + ${MAKE} distclean >/dev/null ${MAKE} -s ${target}_config

Dear Marek Vasut,
When using ccache in MAKEALL, use separate directory for the cache for each board. This way we can avoid rewriting the same files by building other boards.
Signed-off-by: Marek Vasut marex@denx.de Cc: Tom Rini trini@ti.com
This one will need more work, sorry.
Best regards, Marek Vasut

Dear Marek Vasut,
In message 1369070715-9585-3-git-send-email-marex@denx.de you wrote:
- # Use per-board CCACHE directory
- if [ "x${CCACHE}" != "x" ] ; then
Why not simply:
if [ "${CCACHE}" ] ; then
?
export CCACHE_DIR="`${CCACHE} -s | grep "^cache directory" | \
tr -s " " | cut -d " " -f 3`/u-boot/${target}" ;
mkdir -p "${CCACHE_DIR}"
- fi
How can I cleanup all the mess of created files and directories after a build?
Best regards,
Wolfgang Denk

Dear Wolfgang Denk,
Dear Marek Vasut,
In message 1369070715-9585-3-git-send-email-marex@denx.de you wrote:
- # Use per-board CCACHE directory
- if [ "x${CCACHE}" != "x" ] ; then
Why not simply:
if [ "${CCACHE}" ] ; then
?
export CCACHE_DIR="`${CCACHE} -s | grep "^cache directory" | \
tr -s " " | cut -d " " -f 3`/u-boot/${target}" ;
mkdir -p "${CCACHE_DIR}"
- fi
How can I cleanup all the mess of created files and directories after a build?
Ignoring this patch, it's FUBAR, sorry.
Best regards, Marek Vasut
participants (4)
-
Marek Vasut
-
sun york-R58495
-
Wolfgang Denk
-
York Sun