#Two-Phase Locking

##Conservative Two-Phase Locking

• It is a concurrency control method that guarantees serializability.
• The whole list of transactions are know beforehand.
• All the locks are aquired at start of each transaction.
• This ensure no deadlock.

##Basic Two-Phase Locking

• It is a concurrency control method that guarantees serializability.
• The whole list of transactions are know beforehand.
• Locks are aquired as required by each transaction.
• Deadlock prevention is implemented using two strategies: Wait - die and Wound - wait

Usage

• Clone the repository

git clone https://github.com/Mukarr/Two-Phase-Locking.git
cd cd Conservative-Two-Phase-Locking

• Random input transactions generation

python3 generate_tx.py -x [num_transactions] -i [max_instructions] -t [max_time] -v [num_variable]

num_transactions: Total number of transactions to the system.

max_instructions: Maximum number of instruction any transaction can generate.

max_time: Maximum time till which system proceeds.

num_variable: Total number of variable in the system.

• Conservative two-phase Locking

python3 twophase_locking_conservative.py [--verbose]

verbose_output: Print output to screen verboselly

• Basic two-phase Locking with wait-die strategy

python3 twophase_locking_wait_die.py [--verbose]

verbose_output: Print output to screen verboselly

• Basic two-phase Locking with wound-wait strategy

python3 twophase_locking_wound_wait.py [--verbose]

verbose_output: Print output to screen verboselly

All these will take the input generated by generate_tx.py.

Example Usage:

python3 generate_tx.py -x 5 -i 10 -t 10 -v 5 | python3 twophase_locking_conservative.py --verbose

• This will generate a system with 5 transactions, each with maximum of 10 instructions, with 5 variable in total and the system's lifetime being 10 seconds.

• This random set of transactions is piped to twophase_locking_conservative.py, which generates the required schedule.