atomic_thread_map_t Class Reference

Inherits sm_thread_map_t.

Collaboration diagram for atomic_thread_map_t:

[legend]List of all members.

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Detailed Description

Fingerprint for this smthread.

Each smthread_t has a fingerprint. This is used by the deadlock detector. The fingerprint is a bitmap; each thread's bitmap is unique, the deadlock detector ORs fingerprints together to make a "digest" of the waits-for-map. Rather than have fingerprints associated with transactions, we associate them with threads.

This class provides synchronization (protection) for updating the map.

Note:

: If you want to be sure the fingerprints are unique, for the purpose of eliminating false-positives in the lock manager's deadlock detector while debugging something, look at the code in smthread_t::_initialize_fingerprint(), where you can enable some debugging code. (There is no need to make them unique -- if there were, we'd use 1 bit per... -- but if you are debugging something you might want to ensure or detect uniqueness for that purpose.)

Definition at line 142 of file smthread.h.

Public Member Functions
bool	has_reader () const
bool	has_writer () const
void	lock_for_read () const
void	lock_for_write ()
void	unlock_reader () const
void	unlock_writer ()
	atomic_thread_map_t ()
	~atomic_thread_map_t ()
atomic_thread_map_t &	operator= (const atomic_thread_map_t &other)

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The documentation for this class was generated from the following file:

• src/sm/smthread.h

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