VMKlinux Runs Out of Memory when Using an mptsas System with More Than 128 LUNs
Details
For each path from an initiator to a LUN target, a fixed amount of memory is allocated during a scan. The memory is allocated from a fixed-size heap, and if too many paths are created, the demand for memory can exceed this supply. When this happens, some paths will have no memory allocated. They are not reported during a scan. The following error message is displayed:
WARNING: LinSCSI: 1331: Could not allocate command blocks for device 0xXXXXXXXX
Solution
When using a system with mptsas, limit the total number of LUNs used to 128. For all other systems, the limit is 256 LUNs.