This parameter specifies the maximum size of a dump file. The size is specified in operating system blocks
Version | Type | Default | Session Modifiable |
System Modifiable |
7.3.4 | Integer | 10000 | No | No |
8.0.4 | Integer | 10000 | No | No |
8.0.5 | Integer | 10000 | No | No |
8.0.6 | Integer | 10000 | No | No |
8.1.5 | Integer | 10000 | No | No |
8.1.6 | String | UNLIMITED | Yes | Immediate |
8.1.7 | String | UNLIMITED | Yes | Immediate |
9.0.1 | String | UNLIMITED | Yes | Immediate |
9.2.0 | String | UNLIMITED | Yes | Immediate |
The parameter can be set in the initialisation file e.g.
max_dump_file_size = 10000
This limits the trace file to 10000 operating system blocks. If the size of an operating system block is 512 bytes then the trace file is limited to 5mb.
In Oracle 8.1.6 and above the default value of this parameter is UNLIMITED. If the specified size has a suffix of "K" e.g. 1000K then this is the maximum file size in kilobytes; if the specified size has a suffix of "M" e.g. 1M then this is the maximum file size in megabytes. If neither a K or M suffix is specified then it still represents the maximum file size in operating system blocks.
The operating system block size is determined by the constant SSTPBLCK (ssparams.h) which represents the minimum physical block size at device level This varies by platform.
Values include:
Operating System |
Size in Bytes |
NT/2000 | 512 |
Solaris | 512 |
HP/UX | 1024 |
Tru 64 Unix | 1024 |
In Oracle 8.1.6 and above this parameter can be modified at system level e.g.
ALTER SYSTEM SET max_dump_file_size = 10000;
In Oracle 8.1.6 and above it can also be modified at session level e.g.
ALTER SESSION SET max_dump_file_size = 10000;
In Oracle 8.1.6 and above this parameter can also be set to UNLIMITED (the default value e.g.:
ALTER SESSION SET max_dump_file_size = UNLIMITED;
Trace file size can also be set to UNLIMITED using the ORADEBUG UNLIMIT command