Redis server console output clarification?

Question

I'm looking at the redis output console and I'm trying to understand the displayed info : (didn't find that info in the quick guide)

So redis-server.exe outputs this :

/*1*/   [2476] 24 Apr 11:46:28 # Open data file dump.rdb: No such file or directory
/*2*/   [2476] 24 Apr 11:46:28 * The server is now ready to accept connections on port 6379
/*3*/   [2476] 24 Apr 11:42:35 - 1 clients connected (0 slaves), 1188312 bytes in use
/*4*/   [2476] 24 Apr 11:42:40 - DB 0: 1 keys (0 volatile) in 4 slots HT.

• Regarding line #1 - what does the dump.rdb file is used for ? is it the data itself ?
• what is the [2476] number ? it is not a port since line #2 tells port is 6379
• What does (0 slaves) means ?
• in line #3 - 1188312 bytes used - but what is the max value so i'd know overflows ...? is it for whole databases ?
• Line #3 What does (0 volatile) means ?
• Line #4 - why do i have 4 slots HT ? I have no data yet

Answer 1

[2476] - process ID

dump.rdb - redis can persist data by snapshoting, dump.rdb is the default file name http://redis.io/topics/persistence

0 slaves - redis can work in master-slave mode, 0 slaves informs you that there are no slave servers connected

1188312 bytes in use - total number of bytes allocated by Redis using its allocator

0 volatile - redis can set keys with expiration time, this is the count of them

4 slots HT - current hash table size, initial table size is 4, as you add more items hash table will grow