On Thu, 12.12.13 15:20, Marcel Holtmann ([email protected]) wrote: > > Hi Andrey, > > >>>> why do we have to spawn threads or do forks for DNS. This looks all > >>>> pretty expensive. In ConnMan for example we just wrote our own async > >>>> DNS using a mainloop. Works perfectly fine and is dirt cheap. > >>> > >>> Well, we don't fork threads/processes for each call but reuse them. > >>> > >>> What libasyncns does what your solution doesn't do is go via NSS. This > >>> means /etc/hosts, nss-myhostname, nss-ldap, nss-mdns and so on just > >>> work, while that all is lost when doing DNS natively. > >>> > >>> I am pretty sure we should not bypass NSS for this. > >> > >> actually NSS for DNS is pretty nasty stuff. I am pretty sure we should > >> bypass it and create a proper implementation. Is anybody actually using > >> NIS or LDAP for domain name resolution? > >> > > > > Yes, there are solutions that are using LDAP for hostname resolution > > quite heavily - actually are based around LDAP without any > > local /etc/hosts. > > that is extremely heavy and must suck form a latency point of > view. Then again, nothing that a DNS<->LDAP bridge couldn’t easily > support. Since dragging LDAP dependencies into every program that has > to load NSS modules is not a good idea either.
Note that "nscd" was created to deal with the performance of the LDAP setups and also doesn't require loading everything into the same process. Lennart -- Lennart Poettering, Red Hat _______________________________________________ systemd-devel mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/systemd-devel
