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DTSTAMP:20261020T151709Z
DTSTART:20261105T213000Z
DTEND:20261105T221500Z
SUMMARY:Stop Scanning the Whole Topic: Server-Side Filtered Reads for Agent
  Context
LOCATION:Room 2004
DESCRIPTION:David Kjerrumgaard\n\nIt sounds like the simplest request in th
 e world: 'give me every event for order #8675309 in the last 24 hours.' On
  a database that's one indexed query. On your event log? You subscribe to 
 the entire topic\, stream millions of messages you don't want across the n
 etwork\, and throw 99.9% of them away client-side just to find the handful
  you needed. Now multiply that by every entity\, and every agent doing it 
 at once — you've built a gloriously expensive way to filter in exactly t
 he wrong place. This talk is about moving that work where it belongs: the 
 broker. You express the predicate — an ID plus a time window — at subs
 cription time\, and you get back only the messages that match. We'll build
  it end to end: how the broker evaluates predicates without decompressing 
 payloads\, how a time-bounded read maps onto the log's segments and retent
 ion (a wide enough window can reach all the way into cold object storage)\
 , and exactly what you save versus client-side scanning in bandwidth\, con
 nections\, and latency. We'll also stay honest about where this is not a d
 atabase: you're reading an ordered log\, not hitting a secondary index\, a
 nd that shapes ordering\, backpressure\, and the failure modes you'll meet
  at scale — plus when to filter at the broker versus in a function versu
 s the consumer. Why does this matter right now? Because 'give me everythin
 g about entity X in this window' is the workhorse query behind assembling 
 agent context\, reconstructing a user session\, debugging from point-in-ti
 me history\, and pulling audit trails for compliance. Make it cheap and se
 rver-side\, and a whole class of problems you're fighting today gets easie
 r By attending this session\, your contact information may be shared with 
 the sponsor for relevant follow up for this event only.
URL:https://sf26.rmoff.net/s/stop-scanning-the-whole-topic-server-side-filt
 ered-reads-for-80
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