SAP buffer: ABAP program (Program)

What causes this issue?

The program buffer (also called ABAP buffer or PXA buffer) contains the
compiled SAP programs.
You can set the maximum size of the program buffer in the system
parameter <ZH>abap/buffersize</>. The system calculates from this the
maximum number of entries in the buffer directory. Specify the value in
system parameter <ZH>abap/buffersize</> in kilobytes .

How to fix this error?

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

INCLUDE BC_BUFFER_INFO1 OBJECT DOKU ID TX LANGUAGE EN
Typical sizes of the program buffer are between 240.000 and 400.000 KB,
depending on the server's work memory, with development systems
requiring larger buffers. The program buffer can be too small, even if
the system displays free space there. If the hit rate is too low or the
swap is too high, you can change the share of the buffer for small and
large programs in addition to changing the size of the buffer.
INCLUDE BC_BUFFER_INFO2 OBJECT DOKU ID TX LANGUAGE EN

Error message extract from SAP system. Copyright SAP SE.