From: Shawn O. Pearce Date: Wed, 20 Aug 2008 00:03:06 GMT Subject: Re: [PATCH] Make reflog query '@{1219188291}' act as '@{2008/08/19 16:24:51}' Message-ID: <20080820000306.GL24212@spearce.org> In-Reply-To: <7vskt0woat.fsf@gitster.siamese.dyndns.org> Junio C Hamano wrote: > "Shawn O. Pearce" writes: > > > The value 1112911993 was chosen for the limit as it is the commit > > timestamp for e83c516331 "Initial revision of "git" ...". Any > > reflogs in existance should contain timestamps dated later than > > the date Linus first stored Git into itself, as reflogs came about > > quite a bit after that. > > > > Additionally a reflog with 1,112,911,993 record entries is also > > simply not valid. Such a reflog would require at least 87 TB to > > store just the old and new SHA-1 values. So our randomly chosen > > upper limit for @{nth} notation is "big enough" that users will > > not run into it by accident. > > Hmm, would we want to apply that logic to replace the magic "8-digit" rule > in date.c::match_digit()? No. Isn't match_digit() in the code path used by GIT_COMMITTER_DATE? We should handle dates as far back as Sat Mar 3 01:46:40 1973 as seconds-since-epoch to support conversion tools which bring in old history that predates Git's inception. If anything the reflog code should change its test to be the same "8-digit" rule. A reflog of 100,000,000 entries requires at least 7.9G, a threshold which isn't utterly insane (as it fits on a DVD-R) but still is not really reasonable for current Git reflog. -- Shawn.