fix(preprod): Reduce snapshot download concurrency to prevent stream failures#116267
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NicoHinderling merged 1 commit intoMay 27, 2026
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…failures Large snapshots (~40K images) cause the download stream to die after ~15s with an HTTP/2 INTERNAL_ERROR. At 32 workers / 200 batch, the endpoint produces ~157 MB/s and pushes RSS to ~906 MB (past the 600 MB reload_on_rss threshold), overwhelming the HTTP/2 transport layer. Halving to 16 workers / 100 batch reduces both throughput and memory pressure while keeping each batch well within the 90s proxy timeout.
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May 26, 2026
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Reduce
FETCH_MAX_WORKERSfrom 32 → 16 andFETCH_BATCH_SIZEfrom 200 → 100 in the snapshot image download endpoint.Large snapshots (~40K images) cause the streaming download to fail after ~15 seconds with an HTTP/2
INTERNAL_ERROR. The server-side logs show:reload_on_rssthreshold)client_disconnectThe high concurrency causes Python memory fragmentation (32 threads churning through ~600 KB images) that pushes RSS past container limits, and the throughput overwhelms HTTP/2 flow control. Halving both constants reduces memory pressure and data rate while keeping each batch well within the 90s proxy timeout.