From 09363135cbf9e94d3ccf9631fea9d5eba5534a43 Mon Sep 17 00:00:00 2001 From: deeaitch Date: Fri, 5 Jun 2026 16:06:40 -0400 Subject: [PATCH] Closess #10. --- .../03-Two_Sum_Is_Not_About_Numbers/readme.md | 33 ++++++++++++++++--- 1 file changed, 29 insertions(+), 4 deletions(-) diff --git a/analysis/03-Two_Sum_Is_Not_About_Numbers/readme.md b/analysis/03-Two_Sum_Is_Not_About_Numbers/readme.md index 6961a79..787aebf 100644 --- a/analysis/03-Two_Sum_Is_Not_About_Numbers/readme.md +++ b/analysis/03-Two_Sum_Is_Not_About_Numbers/readme.md @@ -281,12 +281,37 @@ See example implementation: ## Example Output -Interview-style reduction: - combines events from different request_id → false positive +``` +Synthetic log stream: + 2026-04-16T10:15:01.100Z service=api event=parse_input latency=12ms request_id=req-1001 + 2026-04-16T10:15:01.110Z service=cache event=cache_miss latency=48ms request_id=req-1001 + 2026-04-16T10:15:01.120Z service=auth event=token_check latency=58ms request_id=req-2001 + 2026-04-16T10:15:01.130Z service=db event=read_user latency=43ms request_id=req-3001 + 2026-04-16T10:15:01.135Z service=db event=read_user latency=55ms request_id=req-1001 + 2026-04-16T10:15:01.144Z service=net event=external_call latency=47ms request_id=req-1001 + 2026-04-16T10:15:01.200Z service=cache event=cache_miss latency=60ms request_id=req-3001 + 2026-04-16T10:15:01.260Z service=net event=external_call latency=52ms request_id=req-3001 -Streaming solution: - finds valid pair within same request and time window +Threshold: 100ms +Time window: 20ms +Interview-style reduction (ignores request_id and time): + first : 2026-04-16T10:15:01.110Z service=cache event=cache_miss latency=48ms request_id=req-1001 + second: 2026-04-16T10:15:01.120Z service=auth event=token_check latency=58ms request_id=req-2001 + combined latency: 106ms + +Streaming sliding-window detection: + first : 2026-04-16T10:15:01.135Z service=db event=read_user latency=55ms request_id=req-1001 + second: 2026-04-16T10:15:01.144Z service=net event=external_call latency=47ms request_id=req-1001 + combined latency: 102ms + +Notes: + - The interview-style version can produce a false correlation. + - In this dataset, it first matches 58ms from req-2001 with 43ms from req-3001. + - That pair exceeds the threshold, but it is operationally meaningless. + - The streaming version only correlates events from the same request_id + and only within the configured time window. +``` --- ## Explanation