kafka is how to achieve high performance read and write?

write

　　 Page caching (page cache) + sequential write disk

　　 Page caching: operating system's memory cache, kafka written is written to the memory cache, then brush from the memory cache to disk

　　 Sequential Write: In general, writing to disk is required to find a suitable disk space. kafka change strategy, added directly in the tail

read

　　 Zero-copy technology

　　 Under normal circumstances, the information disk -> Client, is required:

1. Disk page cache;

1. Page cache to cache software;
2. Software cache to cache socket;
3. socket buffer to the card

kafka direct skip step 2 and Step 3