From: satoshi shiba Date: 2012-02-13T09:25:21+09:00 Subject: [ruby-core:42512] [ruby-trunk - Bug #3924] Performance bug (in require?) Issue #3924 has been updated by satoshi shiba. Hi, Yusuke ENDOH wrote: > Hi, > > 2011/6/23 Hiroshi Nakamura : >> Anyone can imagine a downside of this? It could not work as expected >> if the result of rb_file_expand_path *changes* during require (adding >> a new file during require should work.) Do we need to care such a >> case? > > > As far as I look the patch, paths that are once stored in cache > will never be collected. It may be considered as a kind of > memory leaks. > > I guess that it is not a problem in casual cases. But I'm not sure > if it is really OK. > May I ask current status of this problem? "rb_file_expand_path()" is still a bottleneck of "rb_require_safe()". So, I'm interested in this problem. If memory leak is a problem, how about collecting strings at the time of mark phase. I made a patch which is based on Shyouhei's patch to resolve memory leak. A patch( https://gist.github.com/1805919 ) collects cached strings at the time of mark phase. ---------------------------------------- Bug #3924: Performance bug (in require?) https://bugs.ruby-lang.org/issues/3924 Author: Carsten Bormann Status: Assigned Priority: Normal Assignee: Yuki Sonoda Category: core Target version: 2.0.0 ruby -v: - =begin Running irb < /dev/null in 1.9.2 causes 3016 calls to lstat64. For instance, there is a sequence of 28 repetitions each of lstat calls to all 6 non-empty path prefixes of /opt/local/lib/ruby1.9/1.9.1/irb.rb -- a total of 170 lstats apparently just to load this file; another set of lstats then occurs later for another 18 (times 6) times. Clearly, something is running amok in the calling sequence rb_require_safe -> realpath_rec -> lstat. Another example: Running a simple test with the baretest gem causes 17008 calls to lstat. According to perftools.rb, 80 % of the 1.2 seconds of CPU is used in Kernel#gem_original_require (and another 12 in GC, some of which may be caused by this). =end -- http://bugs.ruby-lang.org/