Subject: Re: [PATCH v7 03/12] update-index: add a new --force-write-index option

From: Junio C Hamano <[email-masked]>
Date: Thu, 21 Sep 2017 11:18:26 +0900

Ben Peart <[email-masked]> writes:

> On 9/20/2017 9:46 PM, Junio C Hamano wrote:
>> Ben Peart <[email-masked]> writes:
>>
>>> Lets see how my ascii art skills do at describing this:
>>
>> Your ascii art is fine.  If you said upfront that the capital
>> letters signify points in time, lower letters are file-touching
>> events, and time flows from left to right, it would have been
>> perfect ;-)
>
> Rats, so close and yet... ;-)

Nah, sorry for forgetting to add "... but I could guess that was the
case after reading a few paragraphs, at which point I rewound and
started reading from the beginning, and it was crystal clear."

> Yes, I suppose we _could_ add a 2nd bit (and then add the logic to set
> that bit every time a fsmonitor change was made) but I don't see that
> it really buys us anything useful.  The force write flag in
> update-index is off by default and the only scenario we have that
> someone would set it is for test cases where the perf of writing out
> the index when it is not needed just doesn't matter.

I tend to agree now.  

My reaction primarily came from that I couldn't quite tell what the
IGNORE_* bit was ment to do and assumed that it meant pretty much
the same thing as existing ones like "valid bit is untrustworthy, so
do not pay attention to it".  It turns out that this one has quite a
different meaning, that is not connected to how much we should trust
state maintained by the fsmonitor, which force me off-track.

Thanks.