DDBMS

DDBMS is a testbed of an OLTP distributed database management system (DBMS). It supports 6 concurrency control algorithms.

This testbed is based on the DBx1000 system, whose concurrency control scalability study can be found in the following paper:

Staring into the Abyss: An Evaluation of Concurrency Control with One Thousand Cores
Xiangyao Yu, George Bezerra, Andrew Pavlo, Srinivas Devadas, Michael Stonebraker
http://voltdb.com/downloads/datasheets_collateral/vdb_whitepaper_staring_into_the_abyss.pdf

Build & Test

To build the database.

make deps
make -j

Configuration

DBMS configurations can be changed in the config.h file. Please refer to README for the meaning of each configuration. Here we only list several most important ones.

NODE_CNT          : Number of server nodes in the database
THREAD_CNT        : Number of worker threads running per server
WORKLOAD          : Supported workloads include YCSB and TPCC
CC_ALG            : Concurrency control algorithm. Six algorithms are supported
                    (NO_WAIT, WAIT_DIE, TIMESTAMP, MVCC, OCC, CALVIN)
MAX_TXN_IN_FLIGHT  : Maximum number of active transactions at each server at a given time
DONE_TIMER        : Amount of time to run experiment

Configurations can also be specified as command argument at runtime. Run the following command for a full list of program argument.

./rundb -h

Run

The DBMS can be run with

./rundb -nid[N]
./runcl -nid[M]

where N and M are the ID of a server and client, respectively

DA

The DBMS can use DA workload. This workload will executes a given sequence of transaction operations and prints out the actual execution results.

To use this workload, you can only use a single node, a single worker thread, and a single messaging thread. Here are some of the configurations that need to be modified in the config.h file

#define NODE_CNT 1
#define THREAD_CNT 1
#define REM_THREAD_CNT 1
#define SEND_THREAD_CNT 1

#define CLIENT_NODE_CNT 1
#define CLIENT_THREAD_CNT 1
#define CLIENT_REM_THREAD_CNT 1
#define CLIENT_SEND_THREAD_CNT 1

#define WORKLOAD DA

In addition, the client and server need to be placed only on one machine! Only two lines of the same IP address can be written in the ifconfig.txt file, and this IP address is the machine you want to test. Here is an example of this file:

10.77.110.148
10.77.110.148

After modifying all the above parameters, the next step is to determine the sequence of transaction operations to be performed. This sequence needs to be written in the input.txt file. Examples are as follows:

W0a R1b W1a R1c C1 W0b C0
R2a R3b W2b W3a C2 C3

A row represents a sequence.

Now to test, you need to perform the following command on the machine which you want to test in:

./rundb -nid0
./runcl -nid1

Finally, check the results, which are output in the commit_histroy.txt file. Compare whether the actual execution results in the file meet the logic of your concurrency control algorithm. If so, it is proved that the algorithm is implemented correctly.