[opt](memory) max_sys_mem_available_low_water_mark_bytesdefault val…

…ue modified to 6.4G (apache#37174)

// The maximum low water mark of the system
`/proc/meminfo/MemAvailable`, Unit byte, default 6.4G,
// actual low water mark=min(6.4G, MemTotal * 10%), avoid wasting too
much memory on machines
// with large memory larger than 64G.
// Turn up max. On machines with more than 64G memory, more memory
buffers will be reserved for Full GC.
// Turn down max. will use as much memory as possible.

be/src/common/config.cpp

@@ -113,12 +113,7 @@ DEFINE_mInt32(max_fill_rate, "2");
 
 DEFINE_mInt32(double_resize_threshold, "23");
 
-// The maximum low water mark of the system `/proc/meminfo/MemAvailable`, Unit byte, default 1.6G,
-// actual low water mark=min(1.6G, MemTotal * 10%), avoid wasting too much memory on machines
-// with large memory larger than 16G.
-// Turn up max. On machines with more than 16G memory, more memory buffers will be reserved for Full GC.
-// Turn down max. will use as much memory as possible.
-DEFINE_Int64(max_sys_mem_available_low_water_mark_bytes, "1717986918");
+DEFINE_Int64(max_sys_mem_available_low_water_mark_bytes, "6871947673");
 
 // The size of the memory that gc wants to release each time, as a percentage of the mem limit.
 DEFINE_mString(process_minor_gc_size, "10%");

be/src/common/config.h

@@ -155,10 +155,10 @@ DECLARE_mInt32(max_fill_rate);
 
 DECLARE_mInt32(double_resize_threshold);
 
-// The maximum low water mark of the system `/proc/meminfo/MemAvailable`, Unit byte, default 1.6G,
-// actual low water mark=min(1.6G, MemTotal * 10%), avoid wasting too much memory on machines
-// with large memory larger than 16G.
-// Turn up max. On machines with more than 16G memory, more memory buffers will be reserved for Full GC.
+// The maximum low water mark of the system `/proc/meminfo/MemAvailable`, Unit byte, default 6.4G,
+// actual low water mark=min(6.4G, MemTotal * 10%), avoid wasting too much memory on machines
+// with large memory larger than 64G.
+// Turn up max. On machines with more than 64G memory, more memory buffers will be reserved for Full GC.
 // Turn down max. will use as much memory as possible.
 DECLARE_Int64(max_sys_mem_available_low_water_mark_bytes);