Remove regex replaces. #12
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Problem: the library spends too much time locking regexes, according to the discussion[1] "If the lock there is dominating performance, then it means the regexp is super trivial. In that case you will get an even bigger speedup by just writing some code instead of doing a regexp match." So, this commit replaces them with traversing the string by each byte O(n) and replacing them. [1] golang/go#8232
artem-cliqz
commented
Feb 8, 2017
| spacingRe = regexp.MustCompile(`[ \r\n\t]+`) | ||
| newlineRe = regexp.MustCompile(`\n\n+`) | ||
| ) | ||
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I would actually not be so radical as to replace the REs at all. They seem to be not too CPU intensive. But as far as the solution works...
| res = append(res, string(current)) | ||
| } | ||
| return strings.Join(res, " ") | ||
| } |
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I would consider using strings.FieldsFunc (used in strings.Fields) as far as we split the string.
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@artem-cliqz Greetings, I appreciate your interest! Did you perform any benchmarking? Would love to see the numbers and if we can get a benefit by avoiding the RE's. Best, |
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@jaytaylor Sorry, I made upstream PR by mistake, it was meant to be within our fork. If it proves useful, we make another PR. Thanks. |
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@artem-cliqz Gotcha, thanks for the info. |
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Problem: the library spends too much time locking regexes, according
to the discussion[1]
"If the lock there is dominating performance, then it means the regexp
is super trivial. In that case you will get an even bigger speedup by
just writing some code instead of doing a regexp match."
So, this commit replaces them with traversing the string by each byte
O(n) and replacing them.
[1] golang/go#8232