Portal routing grain saturates on slow EntityViews/AgenticOffice deliveries — dispatch legs held ~26s with all channel queues and pool gauges at zero #5374

2026-09-22 17:45:17Z memex-portal-deployment-857546649-2c25b crit: MeshWeaver.Hosting.Orleans.RoutingGrain[0]
      [ROUTE] Routing back-pressure [440d2a6b#1 started 2026-09-22T17:45:17.8622331Z]: 64 route dispatches in flight (reporting threshold 64); ordered channels queued 0 over 0 stream destination(s), deepest per-channel queue 0, routing pool subscribing 0, waiting for a pool slot 0; oldest leg in flight 7732 ms — dispatch → EntityViews (delivery l8_b1me9PUm0DMYF3okJ4Q). Latest dispatch target Store/Provision — the address that happened to cross the threshold, NOT a diagnosis. A slot is held from dispatch until the leg terminates, INCLUDING the unbounded wait for a ThreadPool thread before the leg's own timeouts start, so a CPU-starved silo raises this with nothing stuck. A CHANNEL is (destination, stream), so a deepest queue of 1 or more means legs of the SAME stream are blocked behind one another (head-of-line within one channel); 0 means nothing is waiting on anything, so read it as load. Many channels over FEW destinations is a multiplexer hub draining in parallel, which is load too — before issue #5009 those legs shared one channel and read as head-of-line. 🚨 THE TWO POOL GAUGES ANSWER DIFFERENT QUESTIONS AND ONLY ONE SEES THE WAIT NAMED ABOVE — issue #5018. 'subscribing' counts legs inside their SUBSCRIBE PROLOGUE only, so a leg still waiting for a ThreadPool thread and a leg already past its subscribe BOTH read 0 there; 'waiting for a pool slot' is the gauge that sees the pre-subscribe wait. High while subscribing is below the pool's cap is a THREAD shortage; both near zero means the legs are past their subscribe and the wait is downstream I/O. 🚨 READ THE OLDEST LEG FIRST: it is the only load-vs-leak discriminator available from a SINGLE line — every leg young is load the silo is absorbing, one leg minutes old is a slot that never came back and the label names it — whereas the episode stamp below needs a SECOND line to say anything. 🚨 Deepest is sampled AT THE CROSSING, so like the in-flight count it is partly…[truncated]
2026-09-22 17:46:00Z memex-portal-deployment-857546649-2c25b crit: MeshWeaver.Hosting.Orleans.RoutingGrain[0]
      [ROUTE] Routing back-pressure [440d2a6b#2 started 2026-09-22T17:46:00.6127155Z]: 64 route dispatches in flight (reporting threshold 64); ordered channels queued 1 over 1 stream destination(s), deepest per-channel queue 0, routing pool subscribing 0, waiting for a pool slot 0; oldest leg in flight 26136 ms — dispatch → AgenticOffice (delivery semy8voOWUOKkJZH5zJE0Q). Latest dispatch target cache/JrlWjPZHp0C3Q2wuZIz-sQ — the address that happened to cross the threshold, NOT a diagnosis. A slot is held from dispatch until the leg terminates, INCLUDING the unbounded wait for a ThreadPool thread before the leg's own timeouts start, so a CPU-starved silo raises this with nothing stuck. A CHANNEL is (destination, stream), so a deepest queue of 1 or more means legs of the SAME stream are blocked behind one another (head-of-line within one channel); 0 means nothing is waiting on anything, so read it as load. Many channels over FEW destinations is a multiplexer hub draining in parallel, which is load too — before issue #5009 those legs shared one channel and read as head-of-line. 🚨 THE TWO POOL GAUGES ANSWER DIFFERENT QUESTIONS AND ONLY ONE SEES THE WAIT NAMED ABOVE — issue #5018. 'subscribing' counts legs inside their SUBSCRIBE PROLOGUE only, so a leg still waiting for a ThreadPool thread and a leg already past its subscribe BOTH read 0 there; 'waiting for a pool slot' is the gauge that sees the pre-subscribe wait. High while subscribing is below the pool's cap is a THREAD shortage; both near zero means the legs are past their subscribe and the wait is downstream I/O. 🚨 READ THE OLDEST LEG FIRST: it is the only load-vs-leak discriminator available from a SINGLE line — every leg young is load the silo is absorbing, one leg minutes old is a slot that never came back and the label names it — whereas the episode stamp below needs a SECOND line to say anything. 🚨 Deepest is sampled AT THE CROSSING, so like the in-flight co…[truncated]