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floere/hashmemtest1.rb

Last active August 29, 2015 13:56
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Quick hash memory test to understand high memory usage when using hashes in Ruby 1.9.3 and 2.1.0 (regarding newly created strings and old hashes).
Raw
hashmemtest1.rb
# We repeatedly fill a hash.
# We use the same keyspace each time after the first time.
#
# My expectation was that the total memory used would not increase significantly after the first iteration.
#
h = {}
10.times do |i|
100000.times do |i|
h[i.to_s] = [1,2,3]
end
puts "#{"%5i" % i} #{`ps aux | grep -e 'ruby' | grep -v grep`}"
end
Raw
hashmemtest2.rb
# We repeatedly fill a hash.
# We use the same keyspace each time after the first time.
#
# My expectation was that the total memory used would not increase significantly after the first iteration.
#
# Note: In this one, we also clear the hash before filling it.
#
h = {}
10.times do |i|
h.clear
100000.times do |i|
h[i.to_s] = nil
end
puts "#{"%5i" % i} #{`ps aux | grep -e 'ruby' | grep -v grep`}"
end
Raw
hashmemtest3.rb
# This time we also freeze the string key.
#
h = {}
10.times do |i|
100000.times do |i|
h[%q{i.to_s}.freeze] = [1,2,3]
end
puts "#{"%5i" % i} #{`ps aux | grep -e 'ruby' | grep -v grep`}"
end
Raw
results_hanke.txt
hanke@soyuz:hashmemtest: chruby 1.9.3
hanke@soyuz:hashmemtest: ruby hashmemtest1.rb
USER PID %CPU %MEM VSZ RSS TT STAT STARTED TIME COMMAND
0 hanke 11035 5.1 0.1 2469184 19280 s006 S+ 2:26PM 0:00.10 ruby hashmemtest1.rb
1 hanke 11035 32.4 0.1 2469184 22572 s006 S+ 2:26PM 0:00.17 ruby hashmemtest1.rb
2 hanke 11035 47.7 0.1 2478400 22592 s006 S+ 2:26PM 0:00.24 ruby hashmemtest1.rb
3 hanke 11035 56.4 0.1 2478400 22592 s006 S+ 2:26PM 0:00.31 ruby hashmemtest1.rb
4 hanke 11035 60.5 0.1 2478400 22592 s006 S+ 2:26PM 0:00.38 ruby hashmemtest1.rb
5 hanke 11035 60.5 0.1 2478400 22592 s006 S+ 2:26PM 0:00.45 ruby hashmemtest1.rb
6 hanke 11035 59.5 0.1 2478400 22592 s006 S+ 2:26PM 0:00.52 ruby hashmemtest1.rb
7 hanke 11035 63.7 0.1 2478400 22592 s006 S+ 2:26PM 0:00.58 ruby hashmemtest1.rb
8 hanke 11035 67.9 0.1 2478400 22592 s006 S+ 2:26PM 0:00.65 ruby hashmemtest1.rb
9 hanke 11035 71.5 0.1 2478400 22592 s006 S+ 2:26PM 0:00.73 ruby hashmemtest1.rb
hanke@soyuz:hashmemtest: ruby hashmemtest2.rb
USER PID %CPU %MEM VSZ RSS TT STAT STARTED TIME COMMAND
0 hanke 11084 5.6 0.1 2460992 14860 s006 S+ 2:26PM 0:00.10 ruby hashmemtest2.rb
1 hanke 11084 32.5 0.1 2470208 17804 s006 S+ 2:26PM 0:00.17 ruby hashmemtest2.rb
2 hanke 11084 48.4 0.1 2470208 18232 s006 S+ 2:26PM 0:00.25 ruby hashmemtest2.rb
3 hanke 11084 59.1 0.1 2470208 18496 s006 S+ 2:26PM 0:00.33 ruby hashmemtest2.rb
4 hanke 11084 64.0 0.1 2471232 21528 s006 S+ 2:26PM 0:00.40 ruby hashmemtest2.rb
5 hanke 11084 64.0 0.1 2471232 22444 s006 S+ 2:26PM 0:00.47 ruby hashmemtest2.rb
6 hanke 11084 62.1 0.1 2472256 22456 s006 S+ 2:26PM 0:00.55 ruby hashmemtest2.rb
7 hanke 11084 61.9 0.1 2472256 22460 s006 S+ 2:26PM 0:00.62 ruby hashmemtest2.rb
8 hanke 11084 69.9 0.1 2472256 22464 s006 S+ 2:26PM 0:00.70 ruby hashmemtest2.rb
9 hanke 11084 69.7 0.1 2472256 22464 s006 S+ 2:26PM 0:00.77 ruby hashmemtest2.rb
hanke@soyuz:hashmemtest: ruby hashmemtest3.rb
USER PID %CPU %MEM VSZ RSS TT STAT STARTED TIME COMMAND
0 hanke 11133 3.1 0.0 2465852 5828 s006 S+ 2:26PM 0:00.06 ruby hashmemtest3.rb
1 hanke 11133 26.1 0.0 2475068 5852 s006 S+ 2:26PM 0:00.09 ruby hashmemtest3.rb
2 hanke 11133 26.1 0.0 2475068 5852 s006 S+ 2:26PM 0:00.12 ruby hashmemtest3.rb
3 hanke 11133 36.4 0.0 2475068 5852 s006 S+ 2:26PM 0:00.16 ruby hashmemtest3.rb
4 hanke 11133 36.4 0.0 2475068 5856 s006 S+ 2:26PM 0:00.19 ruby hashmemtest3.rb
5 hanke 11133 39.1 0.0 2475068 5856 s006 S+ 2:26PM 0:00.23 ruby hashmemtest3.rb
6 hanke 11133 39.1 0.0 2475068 5856 s006 S+ 2:26PM 0:00.27 ruby hashmemtest3.rb
7 hanke 11133 43.2 0.0 2475068 5856 s006 S+ 2:26PM 0:00.30 ruby hashmemtest3.rb
8 hanke 11133 43.2 0.0 2475068 5856 s006 S+ 2:26PM 0:00.33 ruby hashmemtest3.rb
9 hanke 11133 44.4 0.0 2475068 5856 s006 S+ 2:26PM 0:00.37 ruby hashmemtest3.rb
hanke@soyuz:hashmemtest: chruby 2.1.0
hanke@soyuz:hashmemtest: ruby hashmemtest1.rb
USER PID %CPU %MEM VSZ RSS TT STAT STARTED TIME COMMAND
0 hanke 11192 26.2 0.2 2469972 25800 s006 S+ 2:26PM 0:00.12 ruby hashmemtest1.rb
1 hanke 11192 45.5 0.2 2479188 34112 s006 S+ 2:26PM 0:00.19 ruby hashmemtest1.rb
2 hanke 11192 45.5 0.3 2495572 43824 s006 S+ 2:26PM 0:00.26 ruby hashmemtest1.rb
3 hanke 11192 49.5 0.3 2495572 43824 s006 S+ 2:26PM 0:00.32 ruby hashmemtest1.rb
4 hanke 11192 54.9 0.3 2495572 43832 s006 S+ 2:26PM 0:00.39 ruby hashmemtest1.rb
5 hanke 11192 64.6 0.3 2495572 43832 s006 S+ 2:26PM 0:00.46 ruby hashmemtest1.rb
6 hanke 11192 67.2 0.3 2511956 53348 s006 S+ 2:26PM 0:00.54 ruby hashmemtest1.rb
7 hanke 11192 70.9 0.4 2528340 65316 s006 S+ 2:26PM 0:00.64 ruby hashmemtest1.rb
8 hanke 11192 71.3 0.4 2528340 69452 s006 S+ 2:26PM 0:00.71 ruby hashmemtest1.rb
9 hanke 11192 71.3 0.4 2528340 69452 s006 S+ 2:26PM 0:00.77 ruby hashmemtest1.rb
hanke@soyuz:hashmemtest: ruby hashmemtest2.rb
USER PID %CPU %MEM VSZ RSS TT STAT STARTED TIME COMMAND
0 hanke 11241 23.1 0.1 2460756 19944 s006 S+ 2:26PM 0:00.12 ruby hashmemtest2.rb
1 hanke 11241 44.2 0.2 2460756 25648 s006 S+ 2:26PM 0:00.20 ruby hashmemtest2.rb
2 hanke 11241 53.2 0.2 2469972 30812 s006 S+ 2:26PM 0:00.29 ruby hashmemtest2.rb
3 hanke 11241 62.5 0.2 2469972 30844 s006 S+ 2:26PM 0:00.38 ruby hashmemtest2.rb
4 hanke 11241 65.2 0.2 2469972 30852 s006 S+ 2:26PM 0:00.47 ruby hashmemtest2.rb
5 hanke 11241 67.4 0.2 2469972 30868 s006 S+ 2:26PM 0:00.55 ruby hashmemtest2.rb
6 hanke 11241 70.0 0.2 2469972 30868 s006 S+ 2:26PM 0:00.64 ruby hashmemtest2.rb
7 hanke 11241 71.1 0.2 2469972 31880 s006 S+ 2:26PM 0:00.72 ruby hashmemtest2.rb
8 hanke 11241 71.0 0.2 2469972 31888 s006 S+ 2:26PM 0:00.81 ruby hashmemtest2.rb
9 hanke 11241 71.0 0.2 2469972 31888 s006 S+ 2:26PM 0:00.89 ruby hashmemtest2.rb
hanke@soyuz:hashmemtest: ruby hashmemtest3.rb
USER PID %CPU %MEM VSZ RSS TT STAT STARTED TIME COMMAND
0 hanke 11290 0.0 0.0 2448208 7344 s006 S+ 2:26PM 0:00.05 ruby hashmemtest3.rb
1 hanke 11290 15.9 0.0 2448208 7344 s006 S+ 2:26PM 0:00.07 ruby hashmemtest3.rb
2 hanke 11290 15.9 0.0 2457424 7364 s006 S+ 2:26PM 0:00.09 ruby hashmemtest3.rb
3 hanke 11290 19.8 0.0 2457424 7364 s006 S+ 2:26PM 0:00.10 ruby hashmemtest3.rb
4 hanke 11290 19.8 0.0 2457424 7364 s006 S+ 2:26PM 0:00.12 ruby hashmemtest3.rb
5 hanke 11290 27.0 0.0 2457424 7364 s006 S+ 2:26PM 0:00.14 ruby hashmemtest3.rb
6 hanke 11290 27.0 0.0 2466640 7384 s006 S+ 2:26PM 0:00.15 ruby hashmemtest3.rb
7 hanke 11290 27.0 0.0 2466640 7384 s006 S+ 2:26PM 0:00.17 ruby hashmemtest3.rb
8 hanke 11290 26.7 0.0 2466640 7384 s006 S+ 2:26PM 0:00.18 ruby hashmemtest3.rb
9 hanke 11290 26.7 0.0 2466640 7384 s006 S+ 2:26PM 0:00.20 ruby hashmemtest3.rb
Raw
run
# E.g. run using chruby
#
chruby 1.9.3
ruby hashmemtest1.rb
ruby hashmemtest2.rb
ruby hashmemtest3.rb
chruby 2.1.0
ruby hashmemtest1.rb
ruby hashmemtest2.rb
ruby hashmemtest3.rb
# Compare the memory usage and how it increases.
# Is it as you expected?
#
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