fix: prevent deadlock in Prometheus chunked streaming #700
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When streaming data from Prometheus with large time ranges (> 1 hour), the StreamRowsChunked function would stall after ~100 rows. This was caused by the bwRows channel (buffer size 100) filling up because processBwRows goroutine was never started. The issue occurred because StreamRowsChunked creates a datastream with NewDatastreamContext() and pushes rows directly, bypassing Start() which normally starts the processBwRows goroutine. Changes: - Add StartBwProcessor() public method to Datastream to start the bytes-written processor independently - Call StartBwProcessor() in StreamRowsChunked before pushing rows This ensures the bwRows channel is drained, preventing the producer from blocking when the buffer fills up.
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When streaming data from Prometheus with large time ranges (> 1 hour), the StreamRowsChunked function would stall after ~100 rows. This was caused by the bwRows channel (buffer size 100) filling up because processBwRows goroutine was never started.
The issue occurred because StreamRowsChunked creates a datastream with NewDatastreamContext() and pushes rows directly, bypassing Start() which normally starts the processBwRows goroutine.
Changes:
This ensures the bwRows channel is drained, preventing the producer from blocking when the buffer fills up.
Related: #668