Multicore Memory Caching Issues - Cache Coherency

[@mikem.1688]

So well explained, and the diagrams are awesome. If only all the Operating Systems tutorials on youtube could be this good.

[@yazoo178]

This is exceptionally well explained, particularly because it's such a complex topic.

[@rosepark222]

At 24:05, the author said "declare a little array and sub sum of two with two values and thread one update the first part of the array and the thread two updated second part." and I am wondering what does it mean. Don't we need two sub sums for the first and half part of the original array? What does it mean by having little array?

[@thedanielchen96]

You have the following big array "int bigArray[10000]". Thread1 sums up elements 0~4999 and Thread2 sums up elements 5000~9999. The variable used to store the summation is a single array "int littleArray[2]", where Thread1 writes to littleArray[0] and Thread2 writes to littleArray[1]. In the process of the summation, Thread1 loops through the first 5000 elements of bigArray and increments the value of littleArray[0] by each element it sees. Thread2 applies this as well for the last 5000 elements while writing to littleArray[1]. From the shared memory's perspective, the concurrent writing to littleArray causes the false sharing.

[@piyushkatariya1040]

Great presentation. thank you.

[@amirkeramatian653]

Very instructive! Thanks a lot.

[@yashkumargumashta6061]

Great piece of work ..

[@srnvs]

Thank you

[@Darieee]

nice :D