The collector found the thread waiting for the VBFM latch. The VBFM latch serializes accesses to VSAM buffers and their associated control information.
VSAM Buffer Wait
The collector found the thread waiting in the DL/I VSAM buffer handler. The buffer handler acquires buffers for VSAM database I/O.
The collector found the thread IWAITing for a program isolation (PI) resource. Program isolation is the mechanism which allows databases to be simultaneously accessed, and even updated, by different users.
A PI resource is essentially a DMB number to identify the physical database, and an RBA (relative byte address) to identify the physical block being held. When two programs attempt to access the same PI resource at the same time, one must wait.
Wait HSSP PVT Pool
The collector found the thread executing inside a dependent HSSP BMP region. The thread is waiting for space in the HSSP private pool.
The collector found the thread waiting for the XCNQ latch.
Program isolation uses the XCNQ latch to serialize access to the PI ENQ/DEQ queues and control blocks.