Managing PubSub+ Cache

This section describes how to configure and manage PubSub+ Cache on a Solace PubSub+ event broker that is acting as the Designated Router for the PubSub+ Cache facility.

Operating Limits

The global operating limits for PubSub+ Cache are listed in the table below.

Performance limits such as maximum cache request rates and maximum message rates depend on the messaging patterns and sizes being used, the number of PubSub+ Cache Instances being used for load balancing, and the server hardware on which PubSub+ Cache Instances have been deployed. For further guidance on the expected performance of PubSub+ Cache in your application environment, contact Solace.

PubSub+ Cache scaling limits

Feature	Global Limit	100-tier Limit
Maximum number of Cache Instances on a router	1024	256
Maximum number of Cached Messages per Cached Topic	unlimited	unlimited
Maximum number of Cache Instances per Cache Cluster	16	16
Maximum number of Cache Clusters per Distributed Cache	64	32
Maximum number of Cache Instances supported by the Designated Router across all Message VPNs	1024	256
Maximum number of Cache Clusters per Designated Router	256	32
Maximum number of Distributed Caches per Designated Router	256	32
Maximum number of configured topics per Cache Cluster	1000	100
Maximum number of cached topics per Cache Instance	unlimited	unlimited

Steps to Configure PubSub+ Cache

The following steps show how to configure the main PubSub+ Cache components on the PubSub+ Cache Designated Router through the Solace CLI. The exact steps required will vary depending on your network conditions and preferred configuration.

If you want to use the Global Caching feature, so that client applications can request messages that are cached on remote Distributed Caches, additional configuration information must be provided when configuring Cache Clusters and when modifying PubSub+ Cache Instance configuration files. For more information on the Global Caching feature, see Using Global Caching.

1. Unlock the PubSub+ Cache feature on the Designated Router.

   See Installing PubSub+ Cache.

2. Configure a new or an existing Message VPN.

   See Configuring Message VPNs for Caching.

3. Configure a Distributed Cache in the Message VPN.

   See Configuring Distributed Caches.

4. Configure one or more Cache Clusters within the Distributed Cache.

   See Configuring Cache Clusters.

5. Add subscriptions for the topics that the Cache Clusters will be responsible for listening for.

   See Assigning Topics to Cache Clusters.

6. Configure one or more PubSub+ Cache Instances within the Cache Clusters.

   See Configuring PubSub+ Cache Instances.

7. Modify a copy of the provided configuration file (included with the PubSub+ Cache Instance installation package) for each PubSub+ Cache Instance so that it has the appropriate configuration parameters for communicating with an event broker host. Each modified configuration file must be saved to the Linux system or event broker that the PubSub+ Cache Instance will run on.

   This file provides a PubSub+ Cache Instance with configuration information when PubSub+ Cache service is invoked in the following step. For additional information, see Customizing PubSub+ Cache Instance Configuration Files.

   If you are going to use the Global Caching feature be sure to review, and modify, as necessary, the Global cache request delay and Global cache request time-out parameters. For more information on Global Caching, see Using Global Caching.

8. Following the steps described within the README file (included with the PubSub+ Cache Instance installation package), to install and run the PubSub+ Cache service script on Linux system or event broker with the modified configuration file.
9. Enable the created PubSub+ Cache Instances.

   See Configuring PubSub+ Cache Instances.

10. Enable the created Cache Clusters.

    See Enabling Cache Clusters.

11. Enable the created Distributed Cache.

    See Enabling Distributed Caches.

12. If the Auto Start Mode was not enabled for the PubSub+ Cache Instances that were created, run the start Admin EXEC command at the Distributed Cache level to put all the PubSub+ Cache Instances under the Designated Cache into service. See Performing PubSub+ Cache Administrative Tasks.