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Originally published at Internet.comiReplay enables the testing and/or performance analysis of SQL DB environments by facilitating the capture of live workloads (the actual transactions) and the replaying of those captured workloads against a test DB environment. Before and after performance parameters are additionally collected, enabling the production of comparison reports between the original and test runs, or between subsequent test runs for optimization processes.
Key components of the platform include the central iReplay Server, which receives captured transactions, allows for the pre-processing of those transactions, and launches the actual runs of the captured transactions against the target server; capture software and/or hardware (more below); a Windows-based reporting server; and a Windows-based GUI client for remote interactions with the iReplay Server.
The platform captures workloads by passively listening to actual network traffic; and thus operates independently of-and is agnostic in regards to-application servers or libraries. For light loads, the vendor includes an iCapture software component (Solaris 8/9/10, Linux) that can be loaded directly on the DB host, where the vendor states that it will consume a typical 1% to 3% of the host's overhead. For heavier loads, this iCapture software can be offloaded to a separate machine (Linux), with traffic routed to it via optical splitters or TAPs; removing the overhead requirement against the host DB. And for the heaviest loads, a dedicated capture appliance can be deployed (again, with traffic routed to it via TAP or splitter) with the vendor specifically noting support for the Solera DS-Series Appliance. When a separate appliance is used, the vendor notes that it is possible to combine the iReplay Server and capture functions into the same appliance.
Captured data is sent to the iReplay Server, where it is pre-processed (target IP addresses adjusted, "before" performance metrics gathered, playback rate set, etc.) for replay against the target DB environment. The vendor warns that this target DB should itself be prepared for the receipt of the transactions (i.e., restored to a state identical to the state of the DB when the initial load was captured). The captured data can then be replayed against the target DB, with the platform automatically gathering "after" performance metrics as a result of the played transactions.
Leveraging technology from the vendor's iWatch product, iReplay provides post-replay analysis capabilities in the form of reporting that can compare the original and subsequent runs; with details provided at the run, session, or individual transaction levels. Filtering options allow for the narrowing of result data, with the vendor also noting the availability of trend and summary-level data such as table utilization, error rates, etc. (which can also be compared).
iReplay is available now; with support for Sybase (12.0/12.5/15), Oracle (9i/10g), and UDB/DB2 (V8/V9.1/V9.5). The vendor states that support for MS SQL Server (2000/2005/2008) and Oracle 11g is expected sometime in the second half of 2008. Base pricing is $50,000 for one database type and one OS type.
Visit the Exact Solutions Web Site for further information.Author: DatabaseJournal Staff
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