Memory Buffer Configuration

MTX Buffer Configuration Parameters lists the default MtxBuf sizes that are configured for MATRIXX Engine. MtxBuf is a buffer used in creating MDCs and for I/O operations. A large buffer is used for most messages. If the size of a message exceeds the maximum size of the MtxBuf, additional MtxBufs will be linked together as needed. You can specify the size of the buffers and also the number of buffers available. The size must be a multiple of 1024. The maximum number must be a power of 2.

Only change these values after consulting with your MATRIXX Support representative.

For details about monitoring the memory buffers see the discussions about displaying memory statistics and print_blade_stats.py in MATRIXX Monitoring and Logging.

Memory Buffer Configuration for Price Loader

The Price Loader application uses a local memory pool (not in shared memory) that uses the same buffer size as the huge MTX Buffer pool. A pool comprises segments, where a segment is contiguous memory. The size of this segment is determined by the buffer size multiplied by the number of buffers. You specify the buffer size when answering the question: MtxBuf:What is the size of the huge MtxBuf (in bytes)?. Suppose you configure a huge buffer size of 122880 bytes. You specify the number of buffers when answering the question: MtxBuf:What is the maximum number of huge MtxBufs?. Suppose you set the maximum number of huge buffers to 16384. This means the number of bytes in a segment, in this case, would be 122880 x 16384, or 2,013,265,920 bytes, which is 2GB. A maximum of one segment is permitted. In this scenario, when starting, Price Loader allocates one segment of 2GB for this pool. If Price Loader needs a greater buffer, an out of memory error will be produced.