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Posts with the tag dynamodb:

System Design Weekly 011: May 2021

Highlights Pinterest: Shallow Mirror Kafka MirrorMaker is a tool to replicate Kafka clusters across different regions. Data from different Source Brokers is transferred to MirrorMaker which then sends this data to Destination Brokers in other regions. Pinterest started experiencing scalability issues at some point. Monitoring showed some CPU and memory spikes. During the investigation, it became apparent that most of the CPU time was spent on message decompression and recompression. Memory consumption was often 2-10 times bigger than the actual data being sent.

System Design Weekly 008: May 2021

Highlights DoorDash: Optimizing OpenTelemetry‚Äôs Span Processor for High Throughput and Low CPU Costs With an effort to migrate from the monolith to microservices, there is a need to trace requests between these services. OpenTelemetry is a new project aiming to become a standard. As a request hits a system, OpenTelemetry assigns a unique ID, all the underlying services (called spans) receive the same ID. Spans data is being collected on a local collector, then it’s sent to a collector gateway.

System Design Weekly 002: March 2021

Highlights Cloudflare: The benefits of serving stale DNS entries when using Consul Cloudflare faced an issue with long latencies for DNS responses in certain parts of the world. In addition DNS over TLS is also a factor. They use Unbound as a DNS resolver. For a better failover, they set 30 seconds TTL for such responses. There are two options to solve this problem. The first is prefetching. This means that on each request TTL is checked.