Am 30.04.2012 21:20, schrieb Greg Stein:
On Sun, Apr 29, 2012 at 08:15, Stefan Fuhrmann<eq...@web.de> wrote:
...
The problem is that there is globally available file name
to back the SHM implementation on OSes that need it.
We can only assume write access to some file within the
respective repositories.
Because a given server process may access thousands of
repositories during its lifetime, keeping the SHM data
alive for all of them is not an option, too.
So, we store the new revprop generation as part of each
setrevprop call, i.e. this write will be serialized and the
write order be kept by the repository write lock.
The only racy situation occurs when the data is being read
again but the first one to finish that procedure is guaranteed
to be the only one that initializes the SHM data. Since even
writers will first go through that initialization phase, they
will never operate on stale data.
Is all the above written into some comments or docstrings? It would be
nice to preserve information in the code rather than mailing lists :-)
Added to docstrings in r1345872.
-- Stefan^2.
