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	16024241443	14G,945M,929K
overview	load		none	0	0K	3823846688	3G,574M,721K
overview	query		none	0	0K	109731840	104M,664K
overview	global		none	48909568	46M,659K	48942354	46M,691K
overview	tc/jemalloc_cache		none	1639846952	1563M,901K	-1	-1K
overview	tc/jemalloc_metadata		none	589617600	562M,310K	-1	-1K
overview	sum of all trackers		none	2278374120	2G,124M,846K	-1	-1K
overview	process resident memory		none	3872526336	3G,621M,132K	26298347520	24G,504M,60K
overview	reserve_memory		none	0	0K	-1	-1K
overview	process virtual memory		none	233444421632	217G,421M,972K	233452937216	217G,430M,72K