2276273 - AS Java - How to identify the largest MPI buffer consumer by MPI dump

NetWeaver Java Application Server (AS Java) is not able to handle new requests (e.g. HTTP, HTTPS) because ICM (Internet Communication Manager) is lack of free (non-reserved) MPI (Memory Pipes) buffers.

1) The dev_icm trace shows relevant error messages, indicating MPI buffers are used up, e.g.:
*** WARNING => IcmReadFromConn(id=556/13676): temporarily out of MPI buffers -> roll out
OR

*** ERROR => HttpJ2EETriggerServer: alloc failed: out of MPI blocks

2) You have read the relevant SAP Note regarding MPI buffer configuration:

Below NetWeaver 740:

SAP Note 737625 - Parameter recommendations for Internet Communication Manager (ICM)

As of NetWeaver 740:

SAP Note 2007212 - Tuning SAP Web Dispatcher and ICM for high load

3) The parameter mpi/total_size_MB is already set quite large (e.g. more than 1GB).

NetWeaver Java Application Server (AS Java)

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