On Fri, Jun 19, 2015 at 11:50 AM, Branko Čibej <br...@wandisco.com> wrote:
> On 18.06.2015 21:58, Stefan Fuhrmann wrote: > > One key design element is that the batch fsync > > container owns the open files and will open them > > only once. So, it can not only guarantee that we > > don't need to reopen files for fsync but it can even > > prevent reopening files in cases where different > > functions were to open & close the same as part > > of some bigger functionality. > > Just remember that we've had problems with too many open files in the > past; make sure that your design limits that number to a sane value. > > To give you an idea of the kind of restriction we're talking about, this > is what the newest OSX reports by default: > > $ ulimit -a | grep 'open files' > open files (-n) 256 > > > Not exactly an abundance ... > Yes, I'm aware of that. For FSX, we will open at most 7 file & directory handles in any fsync batch. Basically one for everything that is part of or container for a revision. This is in the same order of magnitude like what we use for delta chains. -- Stefan^2.
