Here is the problem : the memory is duplicated when forking and calling GC in 2.2.1. The main issue here is that I am operating on huge data, going up to 1GB, and when the GC is running and I am forking a process, it is killing my machine since the 1GB becomes 2GB.
We have written a small program that reproduces the issue (see attached file). 1. The program instantiates an object and then forks into two processes. 2. The GC is called in the child process. 3. The memory allocation (as given by /proc/*pid*/smaps) changes from shared to private, thereby indicating a doubling of memory consumption. Here is the output of the program (size is in mb): ruby version 2.2.1 time pid message shared private 4.011s 4723 Parent pre GC 68 0 4.013s 4737 Child pre GC 68 0 8.019s 4723 Parent post GC 5 62 8.093s 4737 Child post GC 5 66 We have tested the program on Ubuntu 14.04 with ruby 1.9.3 and 2.2.1. The tests have been performed on a freshly installed Ubuntu machine with no other software. We have also tried to fork 10 children and see a 10 doubling of the memory consumption, the issue only occurs after running the GC. -- You received this message because you are subscribed to the Google Groups "Ruby on Rails: Core" group. To unsubscribe from this group and stop receiving emails from it, send an email to rubyonrails-core+unsubscr...@googlegroups.com. To post to this group, send email to rubyonrails-core@googlegroups.com. Visit this group at http://groups.google.com/group/rubyonrails-core. For more options, visit https://groups.google.com/d/optout.
mem.rb
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