differential equations - NDsolve memory leak

Every time I run NDsolve it uses some memory that I am not able to free later.

The following is an example code based on the spring equation (Hooke's law) that increases memory usage by 280 bytes each iteration.

$HistoryLength = 0;
tlimit = 1;
x0 = 1;
m = 1;

k = 1;

Do[
  memory1 = MemoryInUse[];
  Print[memory1];
  sol = NDSolve[{x''[t] == -k/m*x[t], x[0] == x0, x'[0] == 0}, x, {t, 0., tlimit}];
  Clear[sol];
  ClearSystemCache[];
  memory2 = MemoryInUse[];
  Print[memory2];

 , {x0, {0, 1, 2, 3}}]

memory2 - memory1

As you can see I have already tried with $HistoryLenght = 0, ClearSystemCache[], Clear[sol]

Does anyone know how to free that memory again so that the memory usage will not increase at every iteration?

Comments

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