Ticket #3972 (closed bug: fixed)
ghc 6.12.1 and 6.13.20090922 consume a lot more memory than 6.10.4 when compiling language-python package
|Reported by:||bjpop||Owned by:||igloo|
|Keywords:||memory usage||Cc:||mle+hs@…, dons@…, overture2112@…, petersen@…, red5_2@…|
|Operating System:||Linux||Architecture:||x86_64 (amd64)|
|Type of failure:||Compile-time performance bug||Difficulty:|
|Test Case:||T3972||Blocked By:|
When compiling the language-python package ghc 6.12.1 and 6.13.20090922 consume a lot more memory than 6.10.4 does.
OS: x86_64 GNU/Linux, Ubuntu 9.10 karmic koala gcc: 4.4.1
All versions of GHC taken from the generic binary downloads provided by the GHC web page.
language-python: 0.2 ( http://projects.haskell.org/language-python/language-python-0.2.tar.gz)
cabal-install version 0.8.0 using version 126.96.36.199 of the Cabal library
Steps taken to witness bug:
- wget http://projects.haskell.org/language-python/language-python-0.2.tar.gz
- tar xvf language-python-0.2.tar.gz
- cd language-python-0.2/
- cabal configure
- cabal build
The build processes 10 files successfully before hitting Language.Python.Common.ParserUtils?. At that point memory consumption grows to at least 1.5 GB resident, and I have to kill the process to prevent my machine from thrashing.
Curiously ParserUtils? is only a relatively small source file, 11975 bytes, 301 lines.
Turing off optimisation on the compilation of ParserUtils? allows it to be compiled very quickly without memory use explosion. But then the build process gets to Language/Python/Version3/Parser/Parser.hs, and ghc consumes lots of memory again (well past 1.5 GB).
This memory consumption behaviour has been independently verified by one other user of language-python on ghc 6.12.1 on a different machine to mine.
However, ghc 6.10.4 can successfully build the entire language-python package in just under 1 GB of ram.