The Extended Decoupler session agent in the Capture Socket Service pipeline manages sustained increases in traffic volume. For websites with sustained increases in traffic volume in the first part of the day or at the end of each month, this session agent is crucial.
Hit volume entering the Short Term Canister is regulated to prevent the STC from becoming overloaded. By queuing data in this manner, CX greatly reduces the loss of data at any point in the pipeline.
Extended Decoupler process
The Extended Decoupler monitors the Short Term Canister vital statistics and compares them to the predefined thresholds for the session agent. When a threshold has been exceeded, Extended Decoupler begins to store hits in a queue. Hits are first queued in memory. When the memory queue reaches its capacity, hits are then queued to disk.
Since the Short Term Canister is an in-memory database, it can sustain volumes above capacity for only 10 to 50 minutes. Beyond this range, the Canister begins paging to disk for extra memory. Paging forces a decrease in the rate at which the Short Term Canister accepts hits, until its capacity is restored.
After Extended Decoupler has gone through the queuing cycle and released hits back into the Canister, hourly reporting is skewed because the Canister looks at the time stamps of when data arrives in the Canister and not when it was originally captured. However, daily reports that tally total hits are not affected by the hourly skewing.
The Extended Decoupler creates a log file in tab-separated format, which can be imported into other applications such as Excel.
The log file also logs CPU usage on the Canister machine for current, last 10 minutes, and last hour metrics.