From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Sun, 14 Feb 2010 19:22:28 GMT
Subject: Re: [PATCH] don't use mmap() to hash files
Message-ID: <alpine.DEB.1.00.1002142021100.20986@pacific.mpi-cbg.de>
In-Reply-To: <37fcd2781002141106v761ce6e0kc5c5bdd5001f72a9@mail.gmail.com>

Hi,

On Sun, 14 Feb 2010, Dmitry Potapov wrote:

> On Sun, Feb 14, 2010 at 9:10 PM, Johannes Schindelin 
> <Johannes.Schindelin@gmx.de> wrote:
> >
> > On Sun, 14 Feb 2010, Dmitry Potapov wrote:
> >
> >> On Sun, Feb 14, 2010 at 02:53:58AM +0100, Johannes Schindelin wrote:
> >> > On Sun, 14 Feb 2010, Dmitry Potapov wrote:
> >> >
> >> > > + if (strbuf_read(&sbuf, fd, 4096) >= 0)
> >> >
> >> > How certain are you at this point that all of fd's contents fit 
> >> > into your memory?
> >>
> >> You can't be sure... In fact, we know mmap() also may fail for huge 
> >> files, so can strbuf_read().
> >
> > That's comparing oranges to apples. In one case, the address space 
> > runs out, in the other the available memory. The latter is much more 
> > likely.
> 
> "much more likely" is not a very qualitative characteristic...

Git was touted as a "content tracker". So I use it as such.

Concrete example: in one of my repositories, the average file size is well 
over 2 gigabytes.

Go figure,
Dscho