Hi, First this is just to investigate things! and if it follows kdbus use cases. This is in the spirit of the late kdbus benchmark threads. Do not apply, just trying to investigate things and if it is really useful.
I did benchmarks and the improvement is say ~50%, but did not post numbers, sorry currently I only have kvm guests under hand! After applying the patches, give test-kdbus-benchmark a try (really sorry). Collecting metadata for kdbus is a heavy operation, in the other hand it is very useful and part of kdbus design. To reduce calls to kdbus_meta_append() and the metadata collection overhead, introduce the KDBUS_HELLO_CACHE_META flag that will only be available to privileged bus users. This flag will permit source connections to use the already cached metadata from the handle or from HELLO instead of collecting the metadata on each send operation. This improves benchmark tests by ~50%. This will be available only to privileged bus users, in other words bus owners. Applications that do not trust the bus owner should not connect to that bus, bus owners are able to monitor to set policies and even impersonate somebody else they can provide custom credential data. This will have dramatic performance improvements on cases where you have a privileged connection that performs broadcast, other unprivileged connections are interested on metadata but will not cause the source connection to collect its data on every send/broadcast round. Use cases where you a privileged process that will setup its environment then opens the bus in order to serve multiple connections and perform broadcasting will benefit from this. It allows to provide metadata and reduce latency. Things to investigate is: Is this really useful Security Add tests Thanks! _______________________________________________ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel