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ruby--ruby/benchmark/bm_io_copy_stream_write.rb
normal f01d3b2334 add benchmark for IO.copy_stream IO#write case
I will attempt to reduce garbage in proposed fix
for https://bugs.ruby-lang.org/issues/13085

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@57237 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
2016-12-31 00:41:14 +00:00

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570 B
Ruby

# The goal of this is to use a synthetic (non-IO) reader
# to trigger the read/write loop of IO.copy_stream,
# bypassing in-kernel mechanisms like sendfile for zero copy,
# so we wrap the /dev/zero IO object:
class Zero
def initialize
@n = 100000
@in = File.open('/dev/zero', 'rb')
end
def read(len, buf)
return if (@n -= 1) == 0
@in.read(len, buf)
end
end
begin
src = Zero.new
dst = File.open(IO::NULL, 'wb')
n = IO.copy_stream(src, dst)
rescue Errno::ENOENT
# not *nix
end if IO.respond_to?(:copy_stream) && IO.const_defined?(:NULL)