Memory usage by subsystem

*Notice:

1. MemTracker only counts the memory on part of the main execution path, which is usually less than the real process memory.

2. each `type` is the sum of a set of tracker values, `sum of all trackers` is the sum of all trackers of all types, .

3. `process resident memory` is the physical memory of the process, from /proc VmRSS VmHWM.

4. `process virtual memory` is the virtual memory of the process, from /proc VmSize VmPeak.

5.`/mem_tracker?type=` to view the memory details of each type, for example, `/mem_tracker?type=query` will list the memory of all queries; `/mem_tracker?type=global` will list the memory of all Cache, metadata and other global life cycles.

see documentation for details.

Type	Label	Parent Label	Limit	Current Consumption(Bytes)	Current Consumption(Normalize)	Peak Consumption(Bytes)	Peak Consumption(Normalize)
experimental			none	0	0K	0	0K
clone			none	0	0K	77824	76K
schema_change			none	0	0K	0	0K
compaction			none	0	0K	2831336049	2G,652M,176K
load			none	0	0K	6984430406	6G,516M,892K
query			none	5590863108	5G,211M,883K	10696767031	9G,985M,237K
global			none	-1609118792	-1534M,589K	5185940339	4G,849M,714K
tc/jemalloc cache			none	700843448	668M,385K	-1	-1K
sum of all trackers			none	4682587764	4G,369M,679K	-1	-1K
process resident memory			none	16129572864	15G,22M,368K	23165071360	21G,587M,956K
process virtual memory			none	87101992960	81G,122M,956K	87504584704	81G,506M,896K