15.2.11 Memory required by in-memory data processing

Use the following formulas to calculate the memory required by in-memory data processing.

For HiRDB/Parallel Server, calculate the RDAREA used as in-memory separately for each server machine.

Formula
  • When shared memory used by the in-memory data buffer is not locked in real memory
Formula 1 + D x 2 (KB)
  • When shared memory used by the in-memory data buffer is locked in real memory
Formula 1 + D x[Figure]([Figure]2,048 [Figure] p[Figure] x p) [Figure] 1,024[Figure] (KB)
Formula 1
  • When shared memory used by the in-memory data buffer is not locked in real memory
n
[Figure]{736 + 32 x A + 48 + 448 x B + 2,048 + C x B} [Figure] 1,024[Figure] (KB)
i=1
  • When shared memory used by in-memory data buffer is locked in real memory
n
[Figure]{[Figure](736 + 32 x A + 48 + 448 x B + 2,048 + C x B) [Figure] p[Figure] x p} [Figure] 1,024[Figure] (KB)
i=1

n: Number of in-memory RDAREAs

A: Number of HiRDB files that constitute an in-memory RDAREAs

B: Total number of pages of in-memory RDAREAs

C: Page size of in-memory RDAREAs

D: Value of Formula 2

p: Page size in a Windows Large Page

Can be checked with the pdntenv command.

Formula 2 (number of shared memory segments used by in-memory data buffer)
[Figure]value of Formula 1 [Figure] (value of SHMMAX operand x 1,024)[Figure]

The value found by Formula 2 is used to calculate the pd_max_resident_rdarea_shm_no operand.