About OMS_HEAP_LIMIT

[Former Member]

Hello,

We have installed our LC (7.6.03 build 12) on a UNIX machine with 57Gb of RAM/ 8CPUs

We decided to put the value 5625000 to the parameter CACHE_SIZE (= 45Gb)

What could we put for the parameter OMS_HEAP_LIMIT ? By default, I think the sapinst will put the same value as the CACHE_SIZE (but in KB) ...

We have the LC installed in the same machine as SAP SCM 5.0 plus it's db Oracle.

Thanks for your answer.

Y.

[Former Member · Accepted solution]

HI,

check following sap note

Note 719652 - Setting initial parameters for liveCache 7.5 or 7.6

Note 833216 - Parameter values as of liveCache versions 7.6 and 7.7

regards,

kaushal

[Former Member · Accepted solution]

Hi Kaushal,

i have already checked that note. But in note

Note 337445 - liveCache and memory management

it says:

4. Calculating OMS_HEAP_LIMIT

Set the liveCache parameter OMS_HEAP_LIMIT to a value greater than 0. The value is specified in KB. The value is specified in KB.

a) Calculation for UNIX (liveCache Version 7.2.5 B08 and higher only) and Windows 64-bit:

Note: When it is started, liveCache allocates memory for the data cache, for example. Other applications that run on the system also require memory. OMS_HEAP_LIMIT should be configured in such a way that the physical memory is sufficient for the areas that have already been allocated (liveCache + other applications) and for the dynamically allocated area.

What I understand is that OMS_HEAP_LIMIT should be at least of the same as the CACHE_SIZE ... Am I wrong ?

[Former Member · Accepted solution]

HI,

OMS_HEAP_LIMIT should be at least of the same as the CACHE_SIZE 

not necessary.

You must ensure that sufficient swap space is configured in the operating system so that the memory request from I/O buffer cache (parameter CACHE_SIZE) and OMS heap (parameter OMS_HEAP_LIMIT) is satisfied

regards,

kaushal

[Former Member · Accepted solution]

Thanks for your answer ... I finally found a "rule of thumb" method in the ADM555 course:

CACHE_SIZE = 40%-60% of RAM

OMS_HEAP_LIMIT = 50% of I/O buffer size

Thanks a lot for your help