[Win32utils-devel] IO.read questions

Daniel Berger djberg96 at gmail.com
Thu May 3 14:48:25 UTC 2012


On Thu, May 3, 2012 at 5:58 AM, Luis Lavena <luislavena at gmail.com> wrote:
> On Thu, May 3, 2012 at 2:25 AM, Daniel Berger <djberg96 at gmail.com> wrote:
>>
>> Oh, I plan on it. In fact I was playing with the ffi branch of the
>> win32-nio library again today. The NIO.read benchmarks are pretty
>> good. Much faster than the default IO.read method.
>>
>
> Please note that NIO.read might not be doing all the legwork IO.read
> is already doing in relation to encodings.
>
> Which, along with others, I think is overkill.

True, I thought that option was a bit silly, since users can always
encode after the fact if they want.

Performance is being hampered somewhat by having to do newline
conversions, but the results are good:

c:\Users\djberge\Repositories\win32-nio>rake bench
ruby -Ilib benchmarks/win32_nio_benchmarks.rb
Small file created (588k)
Medium file created (6mb)
Large file created (58mb)
Huge file created (618mb)

                           user     system      total        real
IO.read(small)         0.016000   0.016000   0.032000 (  0.027001)
IO.read(medium)        0.234000   0.062000   0.296000 (  0.295017)
IO.read(large)         2.184000   0.484000   2.668000 (  2.687154)
IO.read(huge)         22.245000   5.007000  27.252000 ( 27.283561)

NIO.read(small)        0.016000   0.000000   0.016000 (  0.017001)
NIO.read(medium)       0.172000   0.188000   0.360000 (  0.617035)
NIO.read(large)        1.263000   1.014000   2.277000 (  4.820276)
NIO.read(huge)        13.822000   7.909000  21.731000 ( 32.729872)

Minor improvements for smaller files, but the savings gets better as
the files get bigger. It's a shame there's no text mode for
CreateFile.

BTW, using FILE_FLAG_NO_BUFFERING with a sector aligned buffer didn't
yield any noticeable improvements that I could see.

Regards,

Dan


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