SUSE SLES 8/9: - SAP Note

• Setting theSetting the

PHYS_MEMSIZE =1024 PHYS_MEMSIZE =1024

the system calculates the percentage portion of

the system calculates the percentage portion of the resources to be used. For the resources to be used. For a server witha server with 4 GB main memory a value

4 GB main memory a value of 25% (1/4) is calculated, for example; internally, further of 25% (1/4) is calculated, for example; internally, further calculations are made using PHYS_MEMSIZE=25%.

calculations are made using PHYS_MEMSIZE=25%.

•

• If PHYS_MEMSIZE is not set, the entire RAM is available to the instanceIf PHYS_MEMSIZE is not set, the entire RAM is available to the instance (corresponding to PHYS_MEMSIZE = 100%).

(corresponding to PHYS_MEMSIZE = 100%).

Note, however, that a certain inconsistency is apparent when querying the active Note, however, that a certain inconsistency is apparent when querying the active system parameters (for example, transaction RZ10). If PHYS_MEMSIZE does system parameters (for example, transaction RZ10). If PHYS_MEMSIZE does not appear in the SAP

not appear in the SAP system profiles, the default value (64 MB) is displayed assystem profiles, the default value (64 MB) is displayed as the active value. The

the active value. The program actually calculates the above-mentioned systemprogram actually calculates the above-mentioned system parameters based on PHYS_MEMSIZE=100%.

parameters based on PHYS_MEMSIZE=100%.

Note on the configuration of the TMPFS Note on the configuration of the TMPFS

You can activate the TMPFS at operating system level as follows, depending on your You can activate the TMPFS at operating system level as follows, depending on your Linux distribution:

Linux distribution:

1. SUSE SLES 8/9:

Modify the SHMFS_SIZE parameter in /etc/sysconfig/kernel (example:

SHMFS_SIZE="6442450944" or "6G" corresponds to 6 GB TMPFS). The remarks SHMFS_SIZE="6442450944" or "6G" corresponds to 6 GB TMPFS). The remarks below apply to the TMPFS

below apply to the TMPFS dimensioning.dimensioning.

2. Red Hat Enterprise Linux 2.1/3/4 and SUSE SLES 10:

Add the following line to the /etc/fstab file:

tmpfs

tmpfs /dev/shm /dev/shm tmpfs tmpfs size=<size> size=<size> 0 0 00 When specifying the size <size> , you must take

When specifying the size <size> , you must take into account both the availableinto account both the available RAM + Swap and

RAM + Swap and the actual memory requirement of your SAP system. If, for example,the actual memory requirement of your SAP system. If, for example, your machine has 4 GB RAM and 8 GB Swap, you can limit the TMPFS to 6 GB using your machine has 4 GB RAM and 8 GB Swap, you can limit the TMPFS to 6 GB using

size=6G or size=6144M size=6G or size=6144M Take into account that Take into account that

o TMPFS must be smaller than the total of RAM and swapTMPFS must be smaller than the total of RAM and swap

o TMPFS must have a size TMPFS must have a size of at least 2 GB (32 bit) or of at least 2 GB (32 bit) or 8 GB (64 bit)8 GB (64 bit)

o As a recommendation, a size of 75% of RAM + swap can be assumed for As a recommendation, a size of 75% of RAM + swap can be assumed for the TMPFS configuration.

the TMPFS configuration.

A change in the

A change in the size of the TMPFS in the size of the TMPFS in the specified locations only becomes effective after specified locations only becomes effective after the next system reboot. There are

the next system reboot. There are options for avoiding a reboot until further notice:options for avoiding a reboot until further notice:

a) In the case of

a) In the case of changes in the /etc/fstab file, you can activate changes in the /etc/fstab file, you can activate thethe modifications with the following command:

modifications with the following command:

mount -o remount /dev/shm mount -o remount /dev/shm b) In the case of chang

b) In the case of changes in the /etc/sysconfig/kernel file, you can modifyes in the /etc/sysconfig/kernel file, you can modify the size <size> of TMPFS temporarily (until the next reboot)

the size <size> of TMPFS temporarily (until the next reboot) as follows:as follows:

mount -o remount,size=<size> -t shm none /dev/shm mount -o remount,size=<size> -t shm none /dev/shm NOTE:

NOTE: Before you execute the command, Before you execute the command, ensure that /dev/shm is not currently beingensure that /dev/shm is not currently being used by SAP software.

used by SAP software.

After the next reboot, also ensure that the TMPFS mounted under /dev/SHM has After the next reboot, also ensure that the TMPFS mounted under /dev/SHM has sufficient available free memory:

sufficient available free memory:

df -h /dev/shm df -h /dev/shm

Additional information about Memory Management Additional information about Memory Management

1. When the SAP instance

1. When the SAP instance still finds relevant files in /dev/shm when you start it, itstill finds relevant files in /dev/shm when you start it, it will not launch. With newer versions of cleanipc

will not launch. With newer versions of cleanipc (patch level 1 or higher in (patch level 1 or higher in 4.5B4.5B and 4.6D), these files are also cleaned up.

and 4.6D), these files are also cleaned up.

2. With systems that have a lot of main memory, d

2. With systems that have a lot of main memory, discrepancies can occur betweeniscrepancies can occur between the automatic setting of the profile parameters described above and the internal the automatic setting of the profile parameters described above and the internal consistency check. This problem is corrected in 4.5B as of patch level 773, in consistency check. This problem is corrected in 4.5B as of patch level 773, in 4.6D as of patch level 1040 and in 6.20. Until then, you can set the problematic 4.6D as of patch level 1040 and in 6.20. Until then, you can set the problematic parameters manually as a workaround, for example, em/blocksize_KB = 8192.

parameters manually as a workaround, for example, em/blocksize_KB = 8192.

3. Currently, systems with significantly more than 32 GB physical main memory 3. Currently, systems with significantly more than 32 GB physical main memory are not fully supported by the 32-bit Linux k

are not fully supported by the 32-bit Linux kernel. At the moment, these systemsernel. At the moment, these systems should be run with approximately 32 GB

should be run with approximately 32 GB of main memory. This restriction doesof main memory. This restriction does not apply to 64-bit Linux systems.

not apply to 64-bit Linux systems.

4. With SUSE Linux Enterprise Server 7

4. With SUSE Linux Enterprise Server 7 (SLES7), the TMPFS may be mounted(SLES7), the TMPFS may be mounted twice during the boot sequence. This can cause the wrong sizes of the TMPFS and twice during the boot sequence. This can cause the wrong sizes of the TMPFS and thereby cause wrong prerequisites for SAP Memory Management. A solution to thereby cause wrong prerequisites for SAP Memory Management. A solution to this problem is available in the SUSE Support Database port (http://sdb.suse.de) this problem is available in the SUSE Support Database port (http://sdb.suse.de) under the key word "tmpfs" or "shm".

under the key word "tmpfs" or "shm".

5. Linux for zSeries is a 64-bit implementation. In addition, refer to Note 892818.

Available address space for SAP Shared Memory Segments Available address space for SAP Shared Memory Segments

The address space allocation of a

The address space allocation of a process differs, depending on the Linux process differs, depending on the Linux distribution anddistribution and version. This differing behavior is particularly significant in a 32-bit environment

version. This differing behavior is particularly significant in a 32-bit environment because only 4 GB (32 bits) of a process can be "seen", regardless of the main memory because only 4 GB (32 bits) of a process can be "seen", regardless of the main memory built into the machine. In a

built into the machine. In a 64-bit environment, this problem becomes less important due64-bit environment, this problem becomes less important due to the much larger address space

to the much larger address space - instead, the question of performance comes - instead, the question of performance comes to the foreto the fore again.

again.

With SAP Extended Memory or SAP

With SAP Extended Memory or SAP buffers, you must take into account that thisbuffers, you must take into account that this concerns shared memory (SHM) on operating systems, which is why the

concerns shared memory (SHM) on operating systems, which is why the complete user complete user space for this storage type is not available in some circumstances.

space for this storage type is not available in some circumstances.

Therefore, when storage parameters are con

Therefore, when storage parameters are configured from SAP to Linux, the attributes of figured from SAP to Linux, the attributes of the individual Linux versions described in the

the individual Linux versions described in the following can be useful:following can be useful:

•

• SUSE Linux Enterprise Server 8 and SUSE Linux Enterprise Server 8 and 9 (x86 - 32 bit)/Red Hat 9 (x86 - 32 bit)/Red Hat Enterprise LinuxEnterprise Linux 2.1 (x86 - 32 bit)

2.1 (x86 - 32 bit)

Operating system libraries are displayed on address 0x4000 0000

Operating system libraries are displayed on address 0x4000 0000 (1 GB) in the(1 GB) in the 32-bit (4 GB in size) address space. As a

32-bit (4 GB in size) address space. As a result, address space (user space) whichresult, address space (user space) which can be used for applications a

can be used for applications and is 3 GB in size is distributed. Accordingly, thend is 3 GB in size is distributed. Accordingly, the area that can be

area that can be used for SAP SHM is approximately 2 GB used for SAP SHM is approximately 2 GB in size (addressin size (address approximately from 1 GB (0x4000 0000) to

approximately from 1 GB (0x4000 0000) to approximately 3 GB (0xC000 0000)).approximately 3 GB (0xC000 0000)).

In addition, the remaining address space

In addition, the remaining address space (for example, below address of 1 GB)(for example, below address of 1 GB) can still be used for heap memory, if the SAP heap quotas (abap/heap_area_*) are can still be used for heap memory, if the SAP heap quotas (abap/heap_area_*) are set sufficiently high.

set sufficiently high.

•

• Red Hat Enterprise Linux 3 and 4 / SUSE Linux Enterprise Server 10 (x86 - 32Red Hat Enterprise Linux 3 and 4 / SUSE Linux Enterprise Server 10 (x86 - 32 bit)

bit)

Operating system libraries are included in the upper edge

Operating system libraries are included in the upper edge of the user space, so thatof the user space, so that almost the entire user space (approximately 2.8 GB) is available

almost the entire user space (approximately 2.8 GB) is available for SAP sharedfor SAP shared memory segments.

memory segments.

As a result, more memory can be

As a result, more memory can be configured for SAP buffers or SAP extendedconfigured for SAP buffers or SAP extended memory than on other operating systems, for example. However,

memory than on other operating systems, for example. However, it does notit does not provide any more address space, so

provide any more address space, so only a small amount of heap memory can only a small amount of heap memory can bebe allocated after such an increase.

allocated after such an increase.

•

• SUSE Linux Enterprise Server 9 (x86_64 SUSE Linux Enterprise Server 9 (x86_64 - 64 bit) with 32 bit SAP - 64 bit) with 32 bit SAP kernelkernel (46D_EXT)

(46D_EXT)

The 32-bit SAP kernel can "see" only 4 GB of address space here, despite the The 32-bit SAP kernel can "see" only 4 GB of address space here, despite the 64- bit operating system. However, these 4 GB are

bit operating system. However, these 4 GB are completely usable for the SAPcompletely usable for the SAP processes, since the Linux kernel space can be included in the 64-bit address processes, since the Linux kernel space can be included in the 64-bit address

space by the operating system.

On SLES9 (x86_64) with a 32-bit SAP kernel provides approximately 2.6 GB for On SLES9 (x86_64) with a 32-bit SAP kernel provides approximately 2.6 GB for SAP shared memory, since operating system libraries fragment the address space SAP shared memory, since operating system libraries fragment the address space from address 0x5555 5000 (approximately 1.365 GB).

from address 0x5555 5000 (approximately 1.365 GB).

However, the remaining 32-bit address space can be used as heap memory However, the remaining 32-bit address space can be used as heap memory (approximately 1.3 GB), juast as in the 32-bit version of SLES9.

(approximately 1.3 GB), juast as in the 32-bit version of SLES9.

•

• Red Hat Enterprise Linux 4 (x86_64 Red Hat Enterprise Linux 4 (x86_64 - 64 bit) with a 32-bit SAP kernel- 64 bit) with a 32-bit SAP kernel (46D_EXT)

(46D_EXT)

Here, the 32-bit SAP kernel can

Here, the 32-bit SAP kernel can only see 4 GB of the 64only see 4 GB of the 64-bit address space, just as-bit address space, just as is the case for SLES9 on

is the case for SLES9 on the x86_64 platform.the x86_64 platform.

Since the operating system libraries are included at the

Since the operating system libraries are included at the lower edge of the 32-bitlower edge of the 32-bit address space, approximately 3.8 GB are available for SAP shared memory.

address space, approximately 3.8 GB are available for SAP shared memory.

As is the case for RHEL 3 o

As is the case for RHEL 3 on 32 bit, there is relatively less memory space leftn 32 bit, there is relatively less memory space left available for heap memory, depending on the settings of the SAP extended available for heap memory, depending on the settings of the SAP extended memory and the SAP buffer.

memory and the SAP buffer.

•

• 64-bit distributions in general64-bit distributions in general

Currently, only theoretical address space restrictions apply for all integrated Currently, only theoretical address space restrictions apply for all integrated 64- bit platforms (that is, systems that use a 64-bit hardware, a 64-bit operating bit platforms (that is, systems that use a 64-bit hardware, a 64-bit operating

system, and a 64-bit SAP kernel).

Header Data Header Data

Reelleeaasse e SSttaattuuss:: RReelleeaasseed d ffoor r CCuussttoommeer r R

Reelleeaasseed d oonn:: 2211..0055..2200007 17 122::0000::1188 M

Maasstteer r LLaanngguuaaggee:: GGeerrmmaann P

Prriioorriittyy:: RReeccoommmmeennddaattiioonnss//aaddddiittiioonnaal l iinnffoo C

Caatteeggoorryy:: CCoonnssuullttiinngg Pr

Primimarary Cy Comompoponenentnt:: BCBC-O-OP-P-LNLNX LX Lininuxux

Secondary Components:BC-CST-MM Memory Management Secondary Components:BC-CST-MM Memory Management Affected Releases

Affected Releases

Software Software Component

Component ReleaseRelease FromFrom Release Note 722890 - SAPinst or process started by

Note 722890 - SAPinst or process started by SAPinst terminates abnormallySAPinst terminates abnormally Summary

Summary Symptom Symptom

SAPinst or a process started by SAPinst terminates abnormally SAPinst or a process started by SAPinst terminates abnormally Other terms

Other terms

SAPinst, UNIX, 621, 622, 641 SAPinst, UNIX, 621, 622, 641 Reason and Prerequisites Reason and Prerequisites Details:

Details:

Case 1:

Case 1:SAPinst terminates abnormally:SAPinst terminates abnormally:

Occurs only, if you use SAPinst version 621.

Occurs only, if you use SAPinst version 621. If the problem occurs, SAPinst is normallyIf the problem occurs, SAPinst is normally terminated using the signal SIGABRT and a

terminated using the signal SIGABRT and a core file is written. Often the last output of core file is written. Often the last output of SAPinst on the command

SAPinst on the command line is "aborted". There is no error message in line is "aborted". There is no error message in the log file.the log file.

Case 2:

Case 2:A process started by SAPinst terminates abnormally:A process started by SAPinst terminates abnormally:

This problem can occur with SAPinst version 621, 622 and 641.

The process is usually terminated by the signal SIGSEGV and a core file is written. This The process is usually terminated by the signal SIGSEGV and a core file is written. This happens only if the started process is running under another group than that group, under happens only if the started process is running under another group than that group, under which SAPinst runs. Examples of

which SAPinst runs. Examples of

processes that run under a different group are R3load or SDM.

This problem normally occurs only, if the group under which the process is running (for This problem normally occurs only, if the group under which the process is running (for example sapsys or dba) has a

example sapsys or dba) has a very large ID.very large ID.

The error message in the log file shows that the child process has terminated abnormally.

The program to be started by the process was not started. Therefore the program was not The program to be started by the process was not started. Therefore the program was not able to take any action, such as creating its own log files.

able to take any action, such as creating its own log files.

Solution Solution

1. Find out the version of SAPinst using the command sapinst -v.

This note does not apply to SA

This note does not apply to SAPinst version 1.0.Pinst version 1.0.

Procedure for SAPinst version 621:

1. Download the required patch from SAP Service Marketplace (SMP) at 1. Download the required patch from SAP Service Marketplace (SMP) at http://service.sap.com/swdc

http://service.sap.com/swdc

--> Download --> Support Packages and

--> Download --> Support Packages and Patches --> Entry by ApplicationPatches --> Entry by Application

Group --> SAP NetWeaver --> SAP Netweaver components (< SAP NW 04) -->

SAP WEB AS --> SAP WEB AS

SAP WEB AS --> SAP WEB AS 6.20 --> SAP WEB AS ABAP 6.20 --> SAP WEB AS ABAP -->-->

SAP KERNEL 6.20 <32 or 64>-BIT --> < OS > --> Database independent SAP KERNEL 6.20 <32 or 64>-BIT --> < OS > --> Database independent --> SAPINST6201

--> SAPINST6201 --> SAPPROD6201 --> SAPPROD6201

Note that there exists no special unicode

Note that there exists no special unicode version of SAPinst.version of SAPinst.

The non-unicode version is used

The non-unicode version is used for the installation of unicode andfor the installation of unicode and non-unicode systems.

non-unicode systems.

2. Back up the installation directory.

3. Unpack the SAP archives you have downloaded from the SAP 3. Unpack the SAP archives you have downloaded from the SAP ServiceMarketplace into the installation directory and start sapinst ServiceMarketplace into the installation directory and start sapinst from there.

from there.

Procedure for SAPinst version 622: