Parallel Computers Technology Inc. (PCTI) develops and markets performance enhancement middleware products to leverage multiple low cost servers. These include synchronous parallel transaction replication, query load balancing, database server fault tolerance and fault tolerant high performance computing products for companies that require mission critical electronic data processing.

The Product: DB^x™ SQL Load Balancer (DSLB)

DB^x™ SQL Load Balancer (DSLB) is designed to tackle SQL load balancing issues for business intelligence (BI) applications. Our unique dedicated SQL load distribution algorithms eliminate poor performance scalability; poor SQL Server failure handling and can eliminate planned service downtimes.

DSLB elevates query load balancing technologies to a new level: transaction loads can be distributed by sessions or by query. Unlike network load balancers, which were designed for distributing stateless network-bound queries, DSLB maintains concurrent client-server session states at all times. Therefore, using session-based distribution algorithm, any applications requiring temporary database objects (with updates) will work flawlessly. Any SQL Server® in the cluster can be taken offline for repair without ever shutting down service. Query-based load distribution is optimal for stateless web traffic. SQL Server® fault tolerance is automatic. It also allows cluster expansion with zero downtime.

How DB^x™ Works:

DB^x™ is an industrial-strength intelligent database packet processor (gateway). It resides on the network path between database clients and a cluster of database servers. The system will run on a dedicated appliance or as a service co-locate with a SQL Server®. It can be protected using built-in IP-takeover to eliminate the single-point-failure. For most applications, deploying DB^x™ is a plug-and play operation. Cluster configuration and monitoring are done through a Windows-based Control Center.

Key Features:

HIGHER PERFORMANCE AND WIDER RANG OF APPLICATIONS
Comparing client IP-based load balancing and network-based load balancers to DSLB's session-based load balancing, DSLB session-based load balancing can deliver finer balancing granularity which means higher overall performance. DSLB can distribute query loads by sessions or by individual query; therefore it can handle wider range of applications than typical network load balancers.

NON-STOP SERVICE
Since DSLB maintains session states at all times, SQL Server fault tolerance is easily obtained by a simple re-do logic in the application's error handling code. Every SQL Server in the cluster can be taken offline for repair and reconnected for load sharing without ever shutting down the cluster.

SCALABILITY
DSLB gateway comes with a built-in automatic dataset resynchronization tool. You can add SQL Server or rebuild a corrupted SQL Server without ever shutting down the cluster.

PROACTIVE MONITORING FOR SECURE DATA ACCESS
DSLB constantly monitors the health of all database servers by looking for telltale signs of failure. It also monitors all incoming network traffic. Only queries from legitimate sources are to be accepted.

ELIMINATES ALL SINGLE POINTS OF FAILURE
DSLB Load Balancer can be protected by IP-takeover for LAN environments or by DNS for WAN environments.

SERVER CONSOLICATION FRIENDLY
DSLB Load Balancer can be installed as a network appliance or co-locate with SQL Server or other services. It saves you money by leveraging all SQL Server resources for your mission critical applications.

Current Offerings:

1. Standard Edition - 200 or fewer concurrent connections, supports up to 4 servers in a cluster.
2. Enterprise Edition - 500-6000 concurrent connections, supports up to 16 servers in a cluster.

System Requirements:

Operating System: Windows NT/2000/2003 Servers, Standard or Enterprise Editions.
Database Support: SQL Servers 2000 and 2005, Standard and Enterprise Editions.

Download the DB^x™ SQL Load Balancer (DSLB) brochure (PDF, 197 Kb)