Synchronization of Tracelogs in Kaira

Abstract

Main goal of the thesis is to design an extension for Kaira which would enable elimination of inconsistent timestamps in trace files gathered during an execution of an application developed in Kaira and run in a distributed environment. Thesis begins with an introduction to Kaira and profiling and tracing techniques. An analysis of time measurement problem in distributed systems is presented to a reader together with an overview of existing solutions. Simple Logical Clock algorithm is chosen. The integration of algorithm to Kaira is described in detail and the capabilities of implementation are tested on real traced programs executed on a supercomputer. This measurement showed that the real clock deviation between nodes of the selected supercomputer is so high that the algorithm is able only to correct timestamps to a certain extent which leads to a formation of time gaps. In conclusion possible solutions which would enable the algorithm to work with so divergent clocks are presented and one of them is tested.