SharedMemory

OptionValues[Trace]	gives the list of possible tracers
MathLink	trace MathLink events
SendReceive	trace Send/Receive operations
Queueing	trace process scheduling (Queue/Wait)
SharedMemory	trace shared variable access (available only if the VirtualShared package has been loaded)

Tracers.

A SharedMemory trace message has the format

where slave is the kernel that accessed the shared variable, and access describes how the variable was accessed:

The remote kernel asked to change the variable var to val. The new value val was returned.

The remote kernel asked for exclusive access to the variable var, setting it to val. The request was granted because var was currently unused.

The remote kernel asked for exclusive access to the variable var, setting it to val. The request was denied because var already had the different value old set by another process.

For shared downvalues, the expression var in the preceding examples will be a normal expression whose head is the shared downvalue, such as f[...].