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	-669866	-654K	6984430406	6G,516M,892K
query			none	4940116324	4G,615M,268K	10696767031	9G,985M,237K
global			none	-1173858747	-1119M,490K	5185940339	4G,849M,714K
tc/jemalloc cache			none	737044072	702M,921K	-1	-1K
sum of all trackers			none	4502631783	4G,198M,45K	-1	-1K
process resident memory			none	15221194752	14G,180M,64K	23157391360	21G,580M,624K
process virtual memory			none	87002075136	81G,27M,660K	87346180096	81G,355M,828K