Web lists-archives.com

Re: Index files autocompletion too slow in big repositories (w / suggestion for improvement)




Jacob Keller <jacob.keller@xxxxxxxxx> writes:

> On Fri, Apr 14, 2017 at 3:33 PM, Ævar Arnfjörð Bjarmason
> <avarab@xxxxxxxxx> wrote:
>> On Sat, Apr 15, 2017 at 12:08 AM, Carlos Pita <carlosjosepita@xxxxxxxxx> wrote:
>>> This is much faster (below 0.1s):
>>>
>>> __git_index_files ()
>>> {
>>>     local dir="$(__gitdir)" root="${2-.}" file;
>>>     if [ -d "$dir" ]; then
>>>         __git_ls_files_helper "$root" "$1" | \
>>>             sed -r 's@/.*@@' | uniq | sort | uniq
>>>     fi
>>> }
>>>
>>> time __git_index_files
>>>
>>> real    0m0.075s
>>> user    0m0.083s
>>> sys    0m0.010s
>>>
>>> Most of the improvement is due to the simpler, non-grouping, regex.
>>> Since I expect most of the common prefixes to arrive consecutively,
>>> running uniq before sort also improves things a bit. I'm not removing
>>> leading double quotes anymore (this isn't being done by the current
>>> version, anyway) but this doesn't seem to hurt.
>>>
>>> Despite the dependence on sed this is ten times faster than the
>>> original, maybe an option to enable fast index completion or something
>>> like that might be desirable.
>>>
>>> Best regards
>>
>> It's fine to depend on sed, these shell-scripts are POSIX compatible,
>> and so is sed, we use sed in a lot of the built-in shellscripts.
>>
>> I think you should submit this as a patch, see Documentation/SubmittingPatches.
>
> Yea it should be fine to use sed.

As long as the use of "sed" is in line with POSIX.1; I do not think
you need the non-portable "-r" merely to strip out everything that
follow the first slash, so perhaps "s|-r|-e|" with the above (and do
not write backslash after pipe at the end of the line---shell knows
you haven't finished talking to it yet if you end a line with a
pipe, and there is no need for backslash), you'd be golden.