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	0	0K
schema_change			none	0	0K	0	0K
compaction			none	0	0K	1589198522	1515M,591K
load			none	15388608	14M,691K	6925257333	6G,460M,450K
query			none	2563705088	2G,396M,962K	14071443220	13G,107M,587K
global			none	3394791605	3G,165M,538K	6276209565	5G,865M,470K
tc/jemalloc cache			none	928152080	885M,158K	-1	-1K
sum of all trackers			none	6902037381	6G,438M,302K	-1	-1K
process resident memory			none	17361293312	16G,173M,20K	22861680640	21G,298M,612K
process virtual memory			none	75390844928	70G,218M,320K	75793436672	70G,602M,260K