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)
overview	other		none	0	0K	0	0K
overview	schema_change		none	0	0K	0	0K
overview	compaction		none	0	0K	0	0K
overview	load		none	0	0K	344605344	328M,656K
overview	query		none	0	0K	264717248	252M,464K
overview	global		none	85272515	81M,329K	233951644	223M,116K
overview	tc/jemalloc cache		none	692213776	660M,150K	-1	-1K
overview	sum of all trackers		none	777486291	741M,479K	-1	-1K
overview	process resident memory		none	1571725312	1498M,936K	2143006720	2043M,748K
overview	reserved memory		none	0	0K	-1	-1K
overview	process virtual memory		none	30178152448	28G,108M,132K	30178172928	28G,108M,152K