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From:   Stefan Beller <sbeller@google.com>
Date:   Thu, 26 Oct 2017 09:58:51 -0700
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Subject: Re: grep vs git grep performance?
To:     Joe Perches <joe@perches.com>,
        =?UTF-8?B?w4Z2YXIgQXJuZmrDtnLDsCBCamFybWFzb24=?= <avarab@gmail.com>
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+ Avar who knows a thing about pcre (I assume the regex compilation
has impact on grep speed)

On Thu, Oct 26, 2017 at 8:02 AM, Joe Perches <joe@perches.com> wrote:
> Comparing a cache warm git grep vs command line grep
> shows significant differences in cpu & wall clock.
>
> Any ideas how to improve this?
>
> $ time git grep "\bseq_.*%p\W" | wc -l
> 112
>
> real    0m4.271s
> user    0m15.520s
> sys     0m0.395s
>
> $ time grep -r --include=*.[ch] "\bseq_.*%p\W" * | wc -l
> 112
>
> real    0m1.164s
> user    0m0.847s
> sys     0m0.314s
>

I wonder how much is algorithmic advantage vs coding/micro
optimization that we can do.