Identification space for multiple processes

[tshemsedinov]

Running GlobalStorage in multiple processes we need a way to separate identification space using one of the following ways:

• Chunks (centralized chunks service needed)
• Prefix (lower bits sequence fixed for certain server or thread)

Related issue: https://github.com/metarhia/GlobalStorage/issues/6

For example:

• Server id (prefix): 10011
• We start GlobalStorage in 10 threads
• Nearest power of two is 2^4 = 16
• So we can calculate following prefixes for 10 threads:

Thread	Thread prefix	Server Prefix	Combined prefix in hex	Prefix bit length
1	0000	10011	0x13	9
2	1000	10011	0x113	9
3	0100	10011	0x93	9
4	1100	10011	0x193	9
5	010	10011	0x53	8
6	110	10011	0xD3	8
7	001	10011	0x33	8
8	101	10011	0xB3	8
9	011	10011	0x73	8
10	111	10011	0xF3	8

[tshemsedinov]

@belochub not prioritized issue, now we can use one counter in db for all threads, so it it obvious bottleneck but it's as a temporary solution.