Compiling with low ram

[jbtule]

I actually have been testing out gentoo on a VPSLINK1, compiling anything becomes a real challenge and ulimit doesn't help in that regard. Using -O0 (no optimizations) rathern than -O2 optimiziations does help getting more things to compile, however, being low on resources that may just cause more problems down the road. Looking in the gcc manual, gcc has a garbage collection scheme for the ram it uses.

The parameters ggc-min-expand,ggc-min-heapsize are used to determine when gcc should clean up and dealloc it's unused memory and their defaults are percentages of the total system memory (4gigs) so it's no wonder gcc is having problems.

Setting both to 0, causes compilation to be way too slow, however setting ggc-min-heapsize to 8MB and ggc-min-expand to 0 works pretty well on a VPSLINK1 and I haven't had problems emerging anything with -O2 since (other than things that are running other processes other than gcc such python or ruby then i pretty much have to stop all non necessary services, and then maybe I squeak by).

For clarification I added these flags to my CFLAGS in /etc/make.conf

--param ggc-min-expand=0 --param ggc-min-heapsize=8192

[pablasso]

thats a tip worth for the wiki

[AnimalMachine]

I was having a hard time with some compilations lately. This trick solved my problems. Thanks.

[vpslinkdotcom]

Nice find!

[Scott]

Thanks. I'll give this a go.

[Scott]

Damn, still probs.

/bin/sh ./libtool --mode=compile gcc -DHAVE_CONFIG_H -I. -I/var/tmp/portage/binu tils-2.16.1-r3/work/binutils-2.16.1/bfd -I. -D_GNU_SOURCE -DTRAD_CORE -I. -I /var/tmp/portage/binutils-2.16.1-r3/work/binutils-2.16.1/bfd -I/var/tmp/portage/ binutils-2.16.1-r3/work/binutils-2.16.1/bfd/../include -I/var/tmp/portage/binut ils-2.16.1-r3/work/binutils-2.16.1/bfd/../intl -I../intl -W -Wall -Wstrict-pro totypes -Wmissing-prototypes -O2 -march=i686 -pipe -c -o elflink.lo /var/tmp/po rtage/binutils-2.16.1-r3/work/binutils-2.16.1/bfd/elflink.c
gcc -DHAVE_CONFIG_H -I. -I/var/tmp/portage/binutils-2.16.1-r3/work/binutils-2.16 .1/bfd -I. -D_GNU_SOURCE -DTRAD_CORE -I. -I/var/tmp/portage/binutils-2.16.1-r3/w ork/binutils-2.16.1/bfd -I/var/tmp/portage/binutils-2.16.1-r3/work/binutils-2.16 .1/bfd/../include -I/var/tmp/portage/binutils-2.16.1-r3/work/binutils-2.16.1/bfd /../intl -I../intl -W -Wall -Wstrict-prototypes -Wmissing-prototypes -O2 -march= i686 -pipe -c /var/tmp/portage/binutils-2.16.1-r3/work/binutils-2.16.1/bfd/elfli nk.c -fPIC -DPIC -o .libs/elflink.o

cc1: out of memory allocating 444160 bytes after a total of 3899392 bytes
make[3]: *** [elflink.lo] Error 1
make[3]: Leaving directory `/var/tmp/portage/binutils-2.16.1-r3/work/build/bfd'
make[2]: *** [all-recursive] Error 1
make[2]: Leaving directory `/var/tmp/portage/binutils-2.16.1-r3/work/build/bfd'
make[1]: *** [all] Error 2
make[1]: Leaving directory `/var/tmp/portage/binutils-2.16.1-r3/work/build/bfd'
make: *** [all-bfd] Error 2

!!! ERROR: sys-devel/binutils-2.16.1-r3 failed.
!!! Function toolchain-binutils_src_compile, Line 192, Exitcode 2
!!! emake failed
!!! If you need support, post the topmost build error, NOT this status message.

[kelvinn]

I'll admit, I may have taken the long way out of solving the compiling memory problem: distcc

Yea, no joke, I just have my personal machine setup to compile everything on my VPS, and no more memory errors (a make -j12 is pretty handy).

[pablasso]

lol, how effective is that? i never thought about using it on non-local networks, nice idea

[kelvinn]

Pretty effective -- I compiled Apache and PHP from source, with all the extra configs I wanted, on a Link2. I was surprised how quick it compiled as well.

Then again, I don't claim to be a distcc guru, but at least it got the job done.

[scotty]

Wow. Thanks. This is very useful.

My home PC is actually older and slower than VPSLink's server here, but it does have plenty of RAM. I've just tested it getting PHP5 compiled. It did not compile faster, but at least I don't have to worry about running out of virtual memory (or have to shut down services while compiling).