Real memory consumed by buffers and cache (MEMUsedBufCache)
This parameter reports the real memory used by file-system buffers and cache. All the modern UNIX systems (AIX, HP-UX, Linux, and Solaris) allocate free memory dynamically for use by file-system buffers and page cache rather than wasting the physical memory. Whenever applications need more memory, the memory used by buffers and cache is allocated for use by applications. Hence, the memory consumed by buffers and cache is treated as free memory rather than used memory, on these systems.
In the DCM mode, DCM consumes the Buffer Cache Size metric from the Perform Data Collector attribute. The following table lists how the parameter value is calculated in the PSL mode:
Operating system | Calculation |
|---|---|
Linux | MEMUsedBufCache = buffer + cache Here, buffer is the Buffers value from /proc/meminfo and cache is the Cached value from /proc/meminfo. |
AIX | MEMUsedBufCache = file_pages * (page_size / 1024) The values of the variables used in the formula are fetched by running the following commands:
|
The value for this parameter is reported correctly only when the kernel module, bunyip, is loaded on the system. If this module is not loaded, the value for this parameter is reported as zero. This parameter is not available on HP-UX and Solaris, in the PSL collection mode.
Default parameter attributes
Attribute | Default value |
|---|---|
Application class | MEMORY |
Command type | not applicable |
Platform | All |
Icon style | graph |
Unit | KB |
Border range | undefined |
Alarm1 range | undefined |
Alarm2 range | undefined |
Scheduling (poll time) | inherits poll time of collector |
Active at installation | yes |
Parameter type | consumer |
Value set by |
BMC ProactiveNet Performance Management properties
Property | Default value |
|---|---|
Monitor type | Memory |
Key Performance Indicator | No |
Monitor for abnormalities | No |
Graph by default | No |
Availability | No |
Response time | No |
Normal distribution | Yes |
Statistical | Yes |