This is a scenario-based topic describing the clustering architecture for maximizing
throughput of SkyVault services.
This scenario shows a single repository database and content store. There are four nodes with SkyVault/Share and two nodes with Solr search subsystem, all accessing the content simultaneously. This set up provides a higher level of availability, reliability, and scalability, thereby maximizing the throughput of various SkyVault services. Nodes in a cluster are positioned behind a load balancer that delegates requests to cluster members based on any one member’s ability/availability to handle the load.
Each SkyVault/Share instance is deployed into its own Tomcat servlet container. SkyVault
services and CPU runtime footprint are optimized for high throughput under heavy concurrency with
such a deployment. The load balancer fronts the cluster, and directs traffic to the member of the
cluster most able to handle the current request.
Note: All the servers in a cluster should have
static IP addresses assigned to them.
In this deployment scenario the following flows are present:
- Client flow:
- Client sends the request to the main load balancer to reach SkyVault Share application.
- Main load balancer analyses the load and redirects the client to one of Share hosts.
- Main load balancer uses the JSESSIONID cookie to stick the client to one of Share nodes.
- SkyVault Share sends the web scripts requests to the local SkyVault repository instance, renders the page, and returns it to the user via the main load balancer.
- SkyVault internal flow:
- SkyVault repositories intercommunication is done via Hazelcast to replicate caches.
- SkyVault repositories share the same contentstore available via NFS/SAMBA share.
- SkyVault repositories share the same database schema.
- SkyVault Solr flow:
- Tracking tier: Two Solr instances periodically query SkyVault repositories to detect new transactions, fetch new content, and build local Lucene indexes. Tracking is done through Solr load balancer, which analyses the load and distributes it across the SkyVault repositories.
- Search tier: Four SkyVault repository instances query two Solr instances on demand through the Solr load balancer.