Buffer: Percentage usage of buffer memory

What causes this issue?

This monitoring tree element (MTE) shows the percentage of space that
has been allocated in a buffer.

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

Alerts because a buffer is full must be evaluated with care. The reason:
by nature, buffers get full. SAP buffers use intelligent procedures to
replace old cached data with newly-required data. Finally, allocating
too much space to a buffer can cause other problems (operating system
paging) without significantly increasing the hit ratio (buffer quality).
The goal in buffer tuning is therefore to make a buffer large enough to
produce a high hit ratio with low swapping and minimal effect on
operating system paging.
Here are guidelines for deciding when to increase the size of particular
SAP buffers:
Enlarge a buffer if the swap rate (replacement of buffer objects) is
also high and/or the hit ratio is below the target threshold.
Enlarge a buffer if there are frequent alerts in this MTE. Frequent
alerts mean that the SAP buffer displacement mechanism is not able to
create enough free space for efficient buffer operation.
If possible, always increase the space available to the Generic Key
buffer if it becomes full.
The program buffer may be too small even if it still shows free space.
Enlarge the buffer or adjust the division of the buffer into sections
for large and small programs if the hit ratio is too low or swapping is
too high. Development systems need a larger-than-normal program buffer.
Increasing the size of a buffer requires that you do the following:
Change the system profile parameters that size the buffer; and
Increase the size of the SAP shared memory pools in which the buffers
reside. See the CCMS Guide to buffer monitoring (Help -> SAP Library ->
SAP NetWeaver -> Solution Life Cycle Managment -> Solution Monitoring ->
Monitoring in the CCMS -> SAP Buffers) help with these changes.
Monitor operating system paging for significant increases and monitor
SAP memory management MTEs in case of unwanted side effects after you
enlarge SAP buffers.
<DS:TX.SMOI_BUFFER_MANAGEMENT_INFO>Background Information</>

Error message extract from SAP system. Copyright SAP SE.