Abstract: In one embodiment, a method includes receiving a registration request from an application running on a client system. The registration request includes a messaging token associated with a message-distribution server. In response to the received registration request, the messaging token is registered to a user profile on a social-networking system. A push notification is generated for display at the client system. The push notification and the messaging token are sent to the message-distribution server, where the messaging token identifies the client system to the message-distribution server for delivery of the push notification.

Abstract: In one embodiment, a method includes accessing a post associated with a first user of an online social network; extracting n-grams from the post; determining whether the post is associated with a trending topic based on whether one or more of the extracted n-grams are associated with the trending topic; identifying one or more second users, wherein each second user is a first-degree connection of the first user within the online social network and wherein each second user is a subscribing user; generating, for each second user, a live social module comprising the post; and sending, to a system of each second user, the live social module.

Abstract: Systems, methods, and non-transitory computer-readable media can generate subscription information associated with a user and a content item, wherein the subscription information is indicative of the user viewing the content item. The subscription information is stored at a first data center. A determination is made to replicate the subscription information based on replication criteria. The subscription information is replicated to one or more additional data centers based on the making the determination to replicate the subscription information.

Abstract: In one embodiment, a method includes receiving a registration request from an application running on a client system. The registration request includes a messaging token associated with a message-distribution server. In response to the received registration request, the messaging token is registered to a user profile on a social-networking system. A push notification is generated for display at the client system. The push notification and the messaging token are sent to the message-distribution server, where the messaging token identifies the client system to the message-distribution server for delivery of the push notification.

Abstract: In one embodiment, a method includes accessing a post associated with a first user of an online social network; extracting n-grams from the post; determining whether the post is associated with a trending topic based on whether one or more of the extracted n-grams are associated with the trending topic; identifying one or more second users, wherein each second user is a first-degree connection of the first user within the online social network and wherein each second user is a subscribing user; generating, for each second user, a live social module comprising the post; and sending, to a system of each second user, the live social module.