DEB9与DEB10中的内存消耗

Question

在以下C ++程序中，我试图通过将指针逐一1页将较大的内存块分为较小的子盖。在创建子块时，我正在初始化64位结构的变量。我试图在Debian10和Debian9上运行此代码。我观察到的是在DEB9中仅消耗64位存储器，但DEB10消耗了4K的整个页面。 有人可以帮助我理解是什么原因导致这种差异？这可以与内核处理内存的方式有关吗？感谢您提前的帮助。

#include <vector>
#include <stdlib.h>
#include <fcntl.h>
#include <unistd.h>

using namespace std;

typedef unsigned char u8;
typedef unsigned int u32;
typedef unsigned long long u64;

struct e{
   u8* f;
   u64* s;
};
struct se{
   u64 cid;
   void* np;
};
const u64 a = -1;
u32 subchunk = 2878;
u32 subchunkperchunk = 140;
u32 chunksize = 1028096;   //in bytes
u32 TSize = 4096;
u32 eleOfChunk = 50;
u32 eSize = 4096;
u64 x;
vector<e> v;
int it=0;

u64& add(const void* ep)
{
    void* subChunkPtr = (void*) (((u64)ep) / chunksize * chunksize);
    u64 firstElementLocation = ((u64)subChunkPtr) + TSize;
    u32 indexInsideSubChunk = (((u64)ep)-firstElementLocation) / eSize;
    se* elePtr = ((se*)subChunkPtr) + indexInsideSubChunk;
    return elePtr->cid;
}

int main()
{
    int file = open("Result", O_CREAT|O_WRONLY, S_IRWXU);
    dup2(file, 1);
    for (u32 i=0; i<= subchunk/subchunkperchunk; i++)
    {
      u32 eleInCurrChunk;
      if (i != subchunk/subchunkperchunk)
      {
         eleInCurrChunk = subchunkperchunk;
      }
      else
      {
         eleInCurrChunk = subchunk % subchunkperchunk;
         if (eleInCurrChunk == 0)
         {
            break;
         }
      }
      u32 CSize = (eleInCurrChunk+1) * chunksize;
      u8* sp;
      sp = new u8[CSize];
      u8* ssp = sp + (chunksize - ((u64)sp % chunksize));
      for (u32 j = 0; j < eleInCurrChunk; ++j)    //creat block
      {
         u8* scp = ssp + j * chunksize;
         u8* ep = scp + TSize;
         for (u32 k=0; k < eleOfChunk ; ++k)   //creat subblock
         {
             v.push_back(e());
             v[it].f = ep;
             v[it].s = &add(ep);
             add(ep)= a;               //set the 64 bits to high
             ep += eSize;
             ++it;
        }
        system("free -m");
      }
    }
  return 0;
}

Below is the output of the code on deb10
              total        used        free      shared  buff/cache   available
Mem:    7914        1789        4306           0        1819        5826
Swap:         0           0           0
              total        used        free      shared  buff/cache   available
Mem:    7914        1789        4306           0        1819        5826
Swap:         0           0           0
              total        used        free      shared  buff/cache   available
Mem:    7914        1791        4304           0        1819        5824
Swap:         0           0           0
              total        used        free      shared  buff/cache   available
Mem:   7914        1791        4304           0        1819        5824
Swap:        0           0           0
              total        used        free      shared  buff/cache   available
Mem:     7914        1793        4302           0        1819        5822
Swap:         0           0           0
              total        used        free      shared  buff/cache   available
Mem:    7914        1793        4302           0        1819        5822
Swap:         0           0           0
              total        used        free      shared  buff/cache   available
Mem:   7914        1795        4300           0        1819        5820
Swap:         0           0           0
.
.
.
Mem:       7914        4592        1502           0        1819        3022
Swap:           0           0           0
              total        used        free      shared  buff/cache   available
Mem:   7914        4594        1500           0        1819        3020
Swap:       0           0           0
              total        used        free      shared  buff/cache   available
Mem:    7914        4594        1501           0        1819        3021
Swap:        0           0           0
              total        used        free      shared  buff/cache   available
Mem:    7914        4596        1499           0        1819        3019
Swap:        0           0           0
              total        used        free      shared  buff/cache   available
Mem:     7914        4596        1499           0        1819        3019
Swap:           0           0           0
              total        used        free      shared  buff/cache   available
Mem:    7914        4598        1497           0        1819        3017
Swap:         0           0           0

If you check the memory usage on "used"  it is consuming ~4.5G by the end of the iteration.


Below is the output of the code on deb9.
              total        used        free      shared  buff/cache   available
Mem:   7923        1843        4128           4        1951        5776
Swap:       0           0           0
              total        used        free      shared  buff/cache   available
Mem:   7923        1843        4128           4        1951        5776
Swap:       0           0           0
              total        used        free      shared  buff/cache   available
Mem:   7923        1843        4128           4        1951        5776
Swap:        0           0           0
              total        used        free      shared  buff/cache   available
Mem:    7923        1843        4128           4        1951        5776
Swap:         0           0           0
              total        used        free      shared  buff/cache   available
Mem:     7923        1843        4128           4        1951        5776
Swap:          0           0           0
.
.
.

              total        used        free      shared  buff/cache   available
Mem:    7923        1870        4101           4        1952        5750
Swap:         0           0           0
              total        used        free      shared  buff/cache   available
Mem:    7923        1870        4101           4        1952        5750
Swap:         0           0           0
              total        used        free      shared  buff/cache   available
Mem:   7923        1870        4100           4        1952        5750
Swap:        0           0           0
              total        used        free      shared  buff/cache   available
Mem:     7923        1870        4100           4        1952        5750
Swap:         0           0           0
              total        used        free      shared  buff/cache   available
Mem:    7923        1870        4101           4        1952        5750
Swap:       0           0           0
              total        used        free      shared  buff/cache   available
Mem:     7923        1870        4100           4        1952        5750
Swap:         0           0           0

到迭代结束时，它消耗了〜1.8克 从输出中可以看到，DEB9和DEB10之间存在巨大的内存消耗差异。当相同的代码在不同的debian机器上运行时，我想知道为什么这是不同的（即deb9和deb10）。