Loading the challenge…

While this loads — quick one

Every subscriber must get each event. A queue, or pub/sub?

Message queueorPub/Sub

A queue hands each message to exactly one consumer — that is how work is shared out. Pub/sub copies every message to every subscriber.

Loading…

While this loads — quick one

Every subscriber must get each event. A queue, or pub/sub?

Message queueorPub/Sub

A queue hands each message to exactly one consumer — that is how work is shared out. Pub/sub copies every message to every subscriber.

Loading the challenge…

While this loads — quick one

Every subscriber must get each event. A queue, or pub/sub?

Message queueorPub/Sub

A queue hands each message to exactly one consumer — that is how work is shared out. Pub/sub copies every message to every subscriber.

File Sync — system design interview practice — PlayCloudLabs

System designassociate

File Sync

A file-sync service keeps a folder identical across a person's laptop, phone and work computer. Files range from small documents to videos of several gigabytes, and people often change a few bytes of a large file and save it again. Re-sending the whole file on every save would waste bandwidth and take far too long on slow connections. When a file changes on one device, the person's other devices should pick up the change within seconds, without each one repeatedly asking the server whether anything is new. The service must know exactly which version of which file every device has, and a file must never be lost or silently mixed with another.

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