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Your tablespace PSAPBTABD is 92% used. How to increase the free space?


                SAPDBA V3.1I - SAP Database Administration

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                   ORACLE version : 7.3.4.3.0
                   ORACLE_SID     : ALD
                   ORACLE_HOME    : /oracle/ALD
                   DATABASE       : open
                   SAPR3          : 31H, 23 times connected

        a - Startup/Shutdown instance    h - Backup database
        b - Instance information         i - Backup archive logs
        c - Tablespace administration    j - Check (and repair) database
        d - Reorganization               k - Restore/Recovery
        e - Export/import                l - Show/Cleanup
        f - Archive mode                 m - User and Security
        g - Additional functions         n - Help

        q - Quit

        Please select ==>  c


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                        Tablespace administration

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                                                Current value
a - Tablespace:
b - Log checks:                                 no

c - Free space and fragmentation  of all tablespaces
d - Check   free space of objects in all tablespaces
e - Check   free space of objects in tablespace

f - Alter   tablespace Add Datafile
g - Create/drop tablespace

h - Display all tablespaces and datafiles
i - Display raw device drivers in /dev

q - Return

Please select  ==>  a

Enter tablespace name [%] ==> psapbtabd

____________________________________________________________________________

                        Tablespace administration

____________________________________________________________________________


                                                Current value
a - Tablespace:                                 PSAPBTABD
b - Log checks:                                 no

c - Free space and fragmentation  of all tablespaces
d - Check   free space of objects in all tablespaces
e - Check   free space of objects in tablespace PSAPBTABD

f - Alter   tablespace PSAPBTABD Add Datafile
g - Drop    tablespace PSAPBTABD

h - Display all tablespaces and datafiles
i - Display raw device drivers in /dev

q - Return

Please select  ==>  f




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                 Alter tablespace PSAPBTABD add datafile

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                                       Current value

    a  -  File system or raw device:   file system
    b  -  File size:                   2088960 K (larger than free space)
    c  -  Select path:                 /oracle/ALD/sapdata5
    d  -  Alter suggested path:        /oracle/ALD/sapdata5
                                       free space: 3608 K
    e  -  Display current files:       10 files, total (in DB): 77


    s  -  Start (Add datafile)

    q  -  Return

    Please select  ==>  s

Symptom: Error messages in the trace files dev_disp, dev_w, where the texts ShmCreate, not enough core, PXA_NO_MEMORY, etc. appear.

Help: Preventing Swap Space Bottlenecks (only UNIX /NT) or decrease extended memory and/or increase main memory.

The program sappfpar lets you check the minimum and maximum (worst case) swap space requirements for an R/3 application server. It also checks the shared memory requirements and if the parameters em/initial_size_MB and abap/heap_area_total are correctly set. Proceed as follows:

1. To check the instance profile for the R/3 application server, start the program sappfpar from the UNIX command line.

/usr/sap//SYS/exe/run/sappfpar check pf=/usr/sap//SYS/profile/ nr= name= | more

2. The program generates a list. Note the total value for the shared memory in the field Shared memory under Memory requirements estimated. This value corresponds to the size of the shared memory required for this profile, and must be calculated into the shared memory requirements for the new Memory Management.
3. At the end of the list, the program specifies the minimum swap space requirements, the maximum heap memory requirements and the swap space requirements in a worst case scenario:

Total, minimum requirement.....: 169.5 MB (shared memory requirement)
Process local heaps, worst case: 762.9 MB
(is set with abap/heap_area_total )
Total, worst case requirements: 962.5 MB

R/3 application servers are important users of swap space. If the swap space in a host system is used up, serious system problems occur as a result. Therefore, you must monitor swap space usage.

To monitor swap space, you can use either the monitoring tool for host operating systems or the system monitor from the SAP Computing Center Management System (CCMS). The CCMS Alert Monitor, which is available via the system monitor, issues warning messages if the swap space usage exceeds a preset limit. You can also display the present usage.

Also see:

Determining the Swap Space Currently Available

Determining the Swap Space Requirements

An R/3 application server divides its swap space with non-R/3 processes in the host system. The maximum swap space size that an R/3 application server can occupy is determined by the following factors:

• Total size of the extended memory buffer (for example, the program and table buffer)

Typical size: 200 to 500 MB

You can test this using the program sappfpar check pf= .

• Number of work processes in an R/3 server

Each work process requires approximately 12 MB of swap space plus the roll area of the active user context; therefore approximately 20 MB per work process.

• As with parameter
em/initial_size_MB, SAP Extended Memory defines (R/3 Extended Memory pool): This parameter assigns the swap space area that the R/3 System uses for its Extended Memory. The pool has a set size. The total size is allocated directly after starting the application server.

Typical values: approximately 500 MB

• R/3 limits for the local process memory (
Private Memory) for the work processes of an application server Parameter abap/heap_area_total defines these limits (maximum local private (heap) memory that can be assigned to all R/3 work processes) This is the upper limit of the swap memory that can be allocated to the R/3 work processes when they run in PRIV mode and use heap memory. The memory is allocated to the work processes in the application server taking this limit into account. The size used varies based on whether the work processes switch to or are restarted in the PRIV mode, when they leave the PRIV mode.

This parameter lets you foresee when the R/3 System requires swap space. This lets you prevent a critical shortage of swap space. Work processes cannot use heap memory resources anymore than specified in this parameter.

Typical values: 2 - 4 GB

Symptom

Corrective action

Increase the swap space or decrease the R/3 Extended Memory.

If necessary, increase the roll area.

Check if the maximum process size (operating system parameter) is sufficient.

See: Swap Space Bottleneck During R/3 Operation

Symptom:

Various error messages that refer to memory bottlenecks (a swap space bottleneck), for example: System Panic; cmemreserve: reservation overrun; ENOMEM, Not enough core; ENOSPC, No space left on device; SIGDANGER (only under AIX). In the R/3 System, the R/3 system log message "no memory of class perm" is output.

This problem can occur with R/3 processes and external processes as well. The relevant process cannot allocate anymore heap memory. This can lead to the database operation being ended or R/3 work processes being stopped.

In the R/3 System, error messages appear in the developer trace files dev_disp, dev_w, in the system log and in dumps. The following messages may appear: TSV_TNEW_; _NO_ROLL_MEMORY; NO_MEM; NO_MEMORY; RESIZE_EM_ALLOC_ERROR, Storage class PERM.

This problem mostly occurs if background jobs are active with large amounts of data.

Possible Causes

• There is no more swap space available (see
Alert Monitor).
• The highest value for one of the R/3 profile parameters that limit the swap space usage has been exceeded. In this case, the following parameters are relevant:
abap/heap_area_dia, abap/heap_area_nondia and abap/heap_area_total.
• The operating system limits for the process size (segment size) have been exceeded. Under AIX, no more than 256 MB can be allocated and under SINIX no more than 384 MB can be allocated.

Corrective action

Increase the swap space or decrease the R/3 Extended Memory. If the swap space already corresponds to the SAP recommendations, 1.5 to 2 GB may still be required. There should always be several hundred MB of free swap space available. You can reduce the maximum swap space need of the R/3 System by reducing the value of parameter abap_heap_area_total. For more detailed information, see Monitoring the Memory Management System.

You can also distribute the load onto several application servers and increase the roll area. Check if the maximum process size (operating system parameters) is sufficient.

By using the following parameters, you can limit the maximum use of the process-specific memory. This in turn limits the maximum use of swap space by an R/3 application server.

Consider the following parameters:

You can find more information on the functions of these parameters under Limits for Allocating Heap Memory in Functions of the R/3 Memory Management System.

Normally, only background work processes use a large amount of swap space.

Dialog processes do not usually use a lot of swap space, as long as the following conditions apply:

• The R/3 Extended Memory is not used up (set with parameter
em/initial_size_MB); and
• Not many of the user contexts have exceeded the upper limit for using the Extended Memory (set with parameter
ztta/roll_extension).

The following generally applies: The more main memory that an application server has, the better the performance.

Procedure

/usr/sap//SYS/exe/run/memlimits | more

Result

The available swap space is given at the end of the program output in the output line Total available swap space: . The program also specifies, if the amount of swap space is adequate and determines the size of the file segments in the system.

Keyword: BASIS
Title : Virtual Address Space of a Work Process

Keyword: BASIS
Title : Swap Space Bottleneck During SAP Operation