Participated in Tencent's backstage development, never
Asked a lot of processes and threads, process communication. The difference between threads and processes.
Slow and fast queries of the database. (Database optimization layer)
linux's basic commands for processes,
There are also tomcat and jvm
Hash collision resolution. I didn't get into the interviewer's eyes, but the interviewer was very nice.
There is redis on the resume, and I asked about redis. There is also a log record of QQ number login and lower limit, and the algorithm to find out the number of people online at the same time.