Many a times, it happens that Sybase server goes down due to stack trace error causing downtime and business impact. In such cases, case is raised with SAP and they ask us to configure shared memory dump so that when stack trace occurs next time, required details can be captured in the dump file for SAP root cause analysis. Below steps can be followed to setup shared memory dump for Sybase server.

Syntax:

1.Enable the server to generate a shared memory dump on conditions.

1> sp_configure "dump on conditions", 1
2>go

2. Specify the dump condition using sp_shmdumpconfig. The syntax for this stored procedure is:

sp_shmdumpconfig "action", type, value, maximum-dumps, dumpdir, dump_file

Sample Example:

Below is the sample example to setup memory dump for Signal 11 error.

1>sp_shmdumpconfig 'add', 'signal', 11, 1,'/home/dba/scripts/memdump', 'ASESRV_memdump', include_proc
2>go

3. Once shared memory is configured, we can run sp_shmdumpconfig with no parameters to display the current configuration for shared memory dumps.

1> sp_shmdumpconfig
2> go

Configured Shared Memory Dump Conditions

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Signal 11
Maximum Dumps: Default (1)
Dumps since boot: 1
Halt Engines: Default (Halt)
Cluster: Default (Local)
Page Cache: Default (Omit)
Procedure Cache: Include
Unused Space: Default (Omit)
Dump Directory: /home/dba/scripts/memdump
Dump File Name: ASESRV_memdump
Estimated File Size: 50 MB

Current number of conditions: 1
Maximum number of conditions: 10

Configurable Shared Memory Dump Configuration Settings

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Dump on conditions: 1
Number of dump threads: 1
Include errorlog in dump file: 1
Merge parallel files after dump: 1

4. Once the memdump has been collected , please use the following to disable the memdump .

1>sp_configure 'dump on conditions', 0
2>go
1>sp_shmdumpconfig "drop", signal, 11
2>go

You can click here in case you need some more details on configuring shared memory dumps.