Update flow control settings #368
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BigQuery SDK has flow control built into it. It looks like this [line](https://github.com/googleapis/java-bigquerystorage/blob/v2.46.0/google-cloud-bigquerystorage/src/main/java/com/google/cloud/bigquery/storage/v1/ConnectionWorker.java#L547) blocks the calling thread, to backpressure the application thread that is trying to send events to BigQuery. Blocking a thread can be problematic for cats-effect apps, because the thread model expects that compute threads are not used for blocking. Our loader does not need back-pressuring from the sdk, because we already have flow control built into the design of the loader (fs2 is pull-based, not push-based). Therefore flow control settings (`maxOutstandingRequestBytes` and `maxOutstandingElementCount`) are increased to larger than defaults values to avoid thread blocking.
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For visibility... I verbally approved this to @pondzix before he merged it. |
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BigQuery SDK has flow control built into it. It looks like this line blocks the calling thread, to backpressure the application thread that is trying to send events to BigQuery.
Blocking a thread can be problematic for cats-effect apps, because the thread model expects that compute threads are not used for blocking. Our loader does not need back-pressuring from the sdk, because we already have flow control built into the design of the loader (fs2 is pull-based, not push-based).
Therefore flow control settings (
maxOutstandingRequestBytesandmaxOutstandingElementCount) are increased to larger than defaults values to avoid thread blocking.