Re: git cherry improvements suggestions

From: Piotr Krukowiecki <piotr.krukowiecki@gmail.com>
Date: Mar 23, 2011, 19:28 UTC
Message-ID: <AANLkTi=7=QDh0Pe9W4bRcGY5Krg7sBqRcZ2C1YonJSRN@mail.gmail.com>
In-Reply-To: <4D8A0741.9000506@drmicha.warpmail.net>

On Wed, Mar 23, 2011 at 3:44 PM, Michael J Gruber <git@drmicha.warpmail.net> wrote:

Show 49 quoted lines

> Piotr Krukowiecki venit, vidit, dixit 23.03.2011 15:43:
>> On Wed, Mar 23, 2011 at 2:33 PM, Michael J Gruber
>> <git@drmicha.warpmail.net> wrote:
>>> Piotr Krukowiecki venit, vidit, dixit 23.03.2011 14:23:
>>>> Just some stats:
>>>>
>>>>    git log --cherry-mark --left-right --oneline --date-order branch...trunk
>>>>
>>>> lists 1004 commits, takes about 20s and memory peaks to about 670MB
>>>> twice during the run (I'm on linux with AMD Phenom II X4 945)
>>>>
>>>> With limit it prints X last commits (the limiting seems to take place after all
>>>> work, on the output list only).
>>>>
>>>> branch..trunk is 551 commits, the other way is 453 commits.
>>>> 710 commits are found to be "=", 98 "<", 196 ">".
>>>>
>>>> Note, I'm not saying it's too slow, or that it's working incorrectly, I'm just
>>>> giving real-life stats if anyone was interested.
>>>> I suspect such checks won't be done frequently.
>>>
>>> You don't need to say it's slow - I've said so already :(
>>>
>>> http://permalink.gmane.org/gmane.comp.version-control.git/169725
>>
>> In the link above:
>>   git cherry A B: 0.4s
>>   git rev-list --cherry A...B: 1.7s
>>
>> So rev-list is 4.25x slower.
>>
>> In my case it's only 1.23x slower:
>>
>>    $ time git rev-list --cherry branch...trunk  > /tmp/rev-list
>>    real       0m18.627s
>>    user       0m17.710s
>>    sys        0m0.900s
>>
>>    $ time git cherry  branch trunk  > /tmp/cherry
>>    real       0m15.345s
>>    user       0m14.310s
>>    sys        0m1.020s
>>
>>
>
> How's that with > /dev/null (or with --count for rev-list)? Also, how
> many merge bases do you have:
>
> git merge-base --all branch trunk | wc -l

I expect only one - there should be no merges between those two branches.

I will do measurements tomorrow.

-- 
Piotr Krukowiecki