Modeling and analysis of a time-stamp history based certification protocol for concurrency control

An examination is made of a technique to derive the time-stamp or interval of time-stamps dynamically by using limited time-stamp history information to re-order transaction at commit time and to derive a back-shifted time-stamp for certification to reduce read-write conflicts. An analytic model to quantify the performance improvement by comparison with the basic time-stamp certification scheme is developed. Since the committed conflicting transaction may itself be back-shifted, the analytic model needs to estimate the distribution of the back-shift of the certification time-stamp in order to determine the probability of successfully back-shifting a transaction requesting commit. It is shown how this relatively complex protocol can be analyzed using a few simple approximations, validate the analysis through simulations, and the range of parameter values for which this approach is most beneficial is determined