Практический опыт профайлинга и оптимизации производительности Ruby-приложений
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The document discusses Ruby performance profiling, highlighting issues such as slow code due to garbage collection and method calls. It covers tools for optimization, including the use of C extensions, memory profiling, and detailed system tracing methods. Recommendations include utilizing Ruby-prof, kcachegrind, and specific profiling commands for effective performance improvement.
![struct RString {
long len;
char *ptr;
};
Ruby String performance
struct RString {
long len;
char * ptr;
VALUE shared;
};
struct RString {
char ary[RSTRING_EMBED_LEN_MAX +1];
}
RSTRING_EMBED_LEN_MAX = 23](https://image.slidesharecdn.com/rubyperformance-130916051402-phpapp01/85/Ruby-14-320.jpg)
Практический опыт профайлинга и оптимизации производительности Ruby-приложений
- 1. Ruby performance profiling Minsk, SaM Solutions, 2013 Presented by Alexey Tulia @AlexeyTulia, github.com/crible
- 2. Ruby. A programmer’s best friend
- 4. SLOW CODE
- 7. Reasons?
- 8. Garbage collection Slow methods call
- 9. one iteration takes ~ 100ms Garbage collection Need one Gb? Expect 128 GC calls! You lose 128*0,1 = 12,8 sec Allocated memory never returns to the system! runs on every 8Mb of allocated memory
- 10. Garbage collection More objects allocation -> more GC calls -> slow code
- 11. RUBY_HEAP_MIN_SLOTS=8000000 RUBY_GC_MALLOC_LIMIT=10000 Garbage collection tuning performance patches
- 12. Ruby String performance user system total real 21 chars 0.250000 0.000000 0.250000 ( 0.247459) 22 chars 0.250000 0.000000 0.250000 ( 0.246954) 23 chars 0.250000 0.000000 0.250000 ( 0.248440) 24 chars 0.480000 0.000000 0.480000 ( 0.478391) 25 chars 0.480000 0.000000 0.480000 ( 0.479662) 26 chars 0.480000 0.000000 0.480000 ( 0.481211) 27 chars 0.490000 0.000000 0.490000 ( 0.490404)
- 13. Ruby String performance Heap strings Shared strings Embedded strings
- 14. struct RString { long len; char *ptr; }; Ruby String performance struct RString { long len; char * ptr; VALUE shared; }; struct RString { char ary[RSTRING_EMBED_LEN_MAX +1]; } RSTRING_EMBED_LEN_MAX = 23
- 16. What can I do to improve performance? Use C extensions or gems Use plain SQL instead of frameworks Use CPU and memory profiling Use Rubinius or JRuby
- 17. THIS TALK IS ABOUT THE TOOLS TO FIX THE ISSUES
- 18. BEFOREYOU REWRITE SH*T IN SCALA, PROFILE!
- 21. STRACE trace system calls and signals strace -cp <pid> strace -ttTp <pid> -o <file>
- 22. % time seconds uses/call calls errors syscall 50,39 0,00064 0 1197 592 read 34,56 0,00044 0 609 writev 14,96 0,000019 0 1226 epoll_ctl 0,00 0,000000 0 4 close 0,00 0,000000 0 1 select 0,00 0,000000 0 4 socket 0,00 0,000000 0 4 4 connect 0,00 0,000000 0 1057 epoll_wait 100,0 0,000127 4134 596 total strace -cp <pid>
- 23. LTRACE trace dynamic library calls ltrace -F <conf_file> -bg -x <symbol> -p pid
- 24. ltrace -F <conf_file> -bg -x <symbol> -p pid -F <conf_file> int mysql_real_query(addr,string,ulong); void garbage_collect(void); int memcached_set(addr,string,ulong,string,ulong);
- 25. ltrace -x garbage_collect ltrace -x mysql_real_query mysql_real_query(0x1c9e0500, "SET NAMES 'UTF8'", 16) = 0 <0.000324> mysql_real_query(0x1c9e0500, "SET SQL_AUTO_IS_NULL=0", 22) = 0 <0.000322> mysql_real_query(0x19c7a500, "SELECT * FROM `users`", 21) = 0 <1.206506> mysql_real_query(0x1c9e0500, "COMMIT", 6) = 0 <0.000181>
- 26. RUBY-PROF fast code profiler for Ruby
- 27. %self total self child calls name ------------------------------------------------------------------------ 8.39 0.54 0.23 0.31 602 Array#each_index 7.30 0.41 0.20 0.21 1227 Integer#gcd 6.20 0.49 0.17 0.32 5760 Timecell#date 5.11 0.15 0.14 0.01 1 Magick::Image#to_blob RUBY-PROF for CPU
- 28. KCachegrind a tool for visualisation http://kcachegrind.sourceforge.net
- 29. KCachegrind
- 30. KCachegrind
- 32. PERFTOOLS.RB google’s performance tools for ruby code CPUPROFILE=/tmp/myprof pprof --calgrind ./myapp /tmp/myprof gem install perftools.rb RUBYOPT="-r`gem which perftools | tail -1`" ruby my_app.rb
- 33. PERFTOOLS.RB CPUPROFILE_REALTIME = 1 CPU/wall time CPUPROFILE_OBJECTS = 1 CPUPROFILE_METHODS = 1
- 35. Out of the box in Ruby 1.9 GC::Profiler.report
- 36. Out of the box in Ruby 1.9 module «objspace»
- 37. Ruby-prof for memory rvm install 1.9.3-p448 --patch railexpress gem install ruby-prof $ ruby-1.9.3-p448 test.rb Thread ID: 14925700 Fiber ID: 17378400 Total: 3842.242188 Sort by: self_time %self total self wait child calls name 56.94 2187.766 2187.766 0.000 0.000 20000 String#chars 32.79 1259.953 1259.953 0.000 0.000 10000 Array#join 10.17 390.812 390.812 0.000 0.000 10000 Array#shuffle 0.01 3839.391 0.336 0.000 3839.055 1 Integer#times 0.00 1562.766 0.188 0.000 1562.578 10000
- 38. GDB.rb $ sudo gdb.rb 13074 GNU gdb (GDB) 7.0 Reading symbols from /usr/bin/ruby...done. Attaching to program: /usr/bin/ruby, process 13074 0x00007fa8b9cb3c93 in select () from /lib/libc.so.6 (gdb) ruby eval 1+2 2 (gdb) ruby eval Thread.list.count 17 (gdb) ruby objects classes 1 YAML::Syck::Resolver 1 SystemStackError 10 OptionParser::Switch::NoArgument
- 39. What should I remeber before CPU profiling? Turn GC off (GC.disable) do_smth is so slow!!!
- 40. Make it work Make it right Make it fast
- 41. When should I stop performance optimisation? Premature optimization is the root of all evil (c) Donald Knuth
- 42. TOOLS MAKE PROFILING EASIER LEARN THEM, USE THEM