NDB Cluster Configuration Files This is the number of page entries (page references) to allocate. It is specified as a number of 32K pages in  DiskPageBufferMemory . The default is sufficient for most cases but you may need to increase the value of this parameter if you encounter problems with very large transactions on Disk Data tables. Each page entry requires approximately 100 bytes. This determines the amount of space used for caching pages on disk, and is set in the  [ndbd]  or  [ndbd default]  section of the  config.ini  file. Previously, this paraeter was specified as a number of 32 KB pages. Beginning with NDB 8.0.19, it is specified as a number of bytes. If the value for  DiskPageBufferMemory  is set too low in conjunction with using more than the default number of LDM threads in  ThreadConfig  (for example  {ldm=6...} ), problems can arise when trying to add a large (for example 500G) data file to a disk-based  NDB  table, wherein the process takes indefinitely long while occupying one of the CPU cores. This is due to the fact that, as part of adding a data file to a tablespace, extent pages are locked into memory in an extra PGMAN worker thread, for quick metadata access. When adding a large file, this worker has insufficient memory for all of the data file metadata. In such cases, you should either increase  DiskPageBufferMemory , or add smaller tablespace files. You may also need to adjust DiskPageBufferEntries . You can query the  ndbinfo.diskpagebuffer  table to help determine whether the value for this parameter should be increased to minimize unnecessary disk seeks. See Section 23.5.14.27, “The ndbinfo diskpagebuffer Table” , for more information. This parameter determines the amount of memory that is used for log buffers, disk operations (such as page requests and wait queues), and metadata for tablespaces, log file groups,  UNDO  files, and • SharedGlobalMemory Version (or later) NDB 8.0.13 Type or units bytes Default 128M Range 0 - 64T Restart Type N (NDB 8.0.13) Version (or later) NDB 8.0.13 Type or units bytes Default 64M Range 4M - 1T Version (or later) NDB 8.0.19 Type or units bytes Default 64M Range 4M - 16T Restart Type N (NDB 8.0.13) Note • DiskPageBufferMemory 4141