Memory Allocation Observation

[former_member160248]

Hi,

Recently experienced the situation where one of our AIX application servers went into memory distress. The server has been in production for a significant amount of time and there are 4 other servers that share the production load and none have ever experienced this and it is a first for this particular server as well.

Via SM04 observed that a user using only a single session was using 32538 Megabytes of memory. Without looking any further I went to SM50 and cacelled without core the workprocess that was executing this thread.The memory wasnearly instantly cleared up and the server returned to normal operation

My question is with the memory parameter as defined below how could this have happened? I would have thought that long before it got to this point it would have shortdumped with TSV_TNEW_PAGE_ALLOC_FAILED or something similar.

Thanks for any insight,

David

Other Information:

OS = AIX

Physical Memory = 12Gb

Paging Space 20Gb

Memory Parameters:

ztta/roll_area 6500000

ztta/roll_first 1

ztta/short_area 2000000

rdisp/ROLL_SHM 16384

rdisp/PG_SHM 16384

rdisp/PG_LOCAL 150

em/initial_size_MB 16383

em/blocksize_KB 4096

em/address_space_MB 4092

ztta/roll_extension 2000000000

abap/heap_area_dia 10000000

abap/heap_area_nondia 10000000

abap/heap_area_total 2000000000

abap/heaplimit 20000000

[former_member160248]

Sorry, I am evidently not explaining myself very clearly. My question pertains to simply how could a single dialog user (with the parameters and quotas defined) consume almost 32Gb of memory? Why would the user not be contrained?

Thanks,

David

[Former Member]

Hi David,

We got Ur question. U want to know y so much of memory was used by that user.

For that you need to contact that user and need to ask what report he/she was running which caused to occupy so much memory. IF the user also doesn't know why and what, better you contact your application team, who will tell what report is, based on that you can Judge, y it consumed so much of memory.

Regards,

Ravi

[Former Member]

Hi,

It's a memory error. Your system is trying to allocate memory to a program which is requesting space and there isn't enough room for it.

If this is a standard SAP program - send it to OSS, if it is a custom program have a look at the short dump to find out when the memory overflow ocurred and instruct an ABAPper to revise the code accordingly.

Kind Regards

Krishna

[anindya_bose]

Hi David

Try to set abap/heap_area_total to 800MB to 1 GB. Can you please tell me whether any work process is going in to PRIV mode?

TSV_TNEW_PAGE_ALLOC_FAILED ..this shortdump may occur due to unavailibility of PSAPTEMP tablespace.