Re: [libvirt] [PATCH v2 2/2] daemon: Introduce max_anonymous_clients

On 04.03.2014 12:56, Daniel P. Berrange wrote: >On Mon, Mar 03, 2014 at 06:22:44PM +0100, Michal Privoznik wrote: >>https://bugzilla.redhat.com/show_bug.cgi?id=981729 >> >>This config tunable allows users to determine the maximum number of >>accepted but yet not authenticated users. >> >>Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com&gt; >>--- >> daemon/libvirtd-config.c | 1 + >> daemon/libvirtd-config.h | 1 + >> daemon/libvirtd.aug | 1 + >> daemon/libvirtd.c | 1 + >> daemon/libvirtd.conf | 4 ++++ >> daemon/test_libvirtd.aug.in | 1 + >> src/locking/lock_daemon.c | 3 +-- >> src/lxc/lxc_controller.c | 2 +- >> src/rpc/virnetserver.c | 52 +++++++++++++++++++++++++++++++++++++++++++-- >> src/rpc/virnetserver.h | 1 + >> 10 files changed, 62 insertions(+), 5 deletions(-) >> >>diff --git a/daemon/libvirtd-config.c b/daemon/libvirtd-config.c >>index c816fda..04482c5 100644 >>--- a/daemon/libvirtd-config.c >>+++ b/daemon/libvirtd-config.c >>@@ -415,6 +415,7 @@ daemonConfigLoadOptions(struct daemonConfig *data, >> GET_CONF_INT(conf, filename, max_workers); >> GET_CONF_INT(conf, filename, max_clients); >> GET_CONF_INT(conf, filename, max_queued_clients); >>+ GET_CONF_INT(conf, filename, max_anonymous_clients); >> >> GET_CONF_INT(conf, filename, prio_workers); >> > >You need a 'data->max_anonymous_clients = 20' initialization somewher >in this file, otherwise it'll default to 0. And I think we want to leave it that way. The value of zero means the feature is disabled. That is, libvirt won't take any actions if count of anonymous clients exceed certain value. It will still take an action though if the number of total clients (both auth and unauth) exceeds max_clients. The action is stop accept()-ing new clients. Trying to invent a bright formula to compute the correct value may lead to us adapting to a certain use case while forgetting about other. And we've been there before (remember 'Set reasonable RSS limit on domain startup'?). If a specific management application using libvirt requires these values it should set it explicitly in the config file rather than relying on libvirt defaults (which would change as libvirt adapts to different management application). What we can do is change the commented default value in config file. Is that what you had in mind in the first place?

The sensible default is zero in my opinion. If management application wants to override this, they still can set the value in the config and then softly reset libvirtd (by softly I mean sending it signal to reload the config).