A note on the performance analysis of static locking in distributed database systems

Even though transaction deadlocks can severely affect the performance of distributed database systems, many current evaluation techniques ignore this aspect. Shyu and Li proposed an evaluation method which takes deadlocks into consideration. However, their technique is limited to exclusive locking. Using this technique, researchers illustrate the impact of deadlocks in the presence of shared locking on distributed database performance

Explaining Reform Deadlocks

Countries are often slow to adjust their economic structures to new necessities although this reform reluctance is costly in terms of growth and employment. This paper analyses the relevant factors that block or foster economic reforms. Theoretical considerations show that there are at least three classes of potentially relevant factors: the objective need for reforms, political-economic issues and factors associated with limited rationality or rational ignorance. In the empirical analysis, a reform event is quantified as a significant change of the Economic Freedom of the World indicator within a five-year-period. This allows to run probit estimations for a large country panel starting in the 1970s where the probability of reform is explained by a number of proxies covering all three classes of potential factors. The results suggest that the initial extent of economic freedom and growth performance are empirically relevant factors. Furthermore, countries with an ageing population appear to behave less reform friendly. --economic policy reforms,economic freedom,reform resistance,limited rationality

Dynamic Choreographies - Safe Runtime Updates of Distributed Applications

Programming distributed applications free from communication deadlocks and races is complex. Preserving these properties when applications are updated at runtime is even harder. We present DIOC, a language for programming distributed applications that are free from deadlocks and races by construction. A DIOC program describes a whole distributed application as a unique entity (choreography). DIOC allows the programmer to specify which parts of the application can be updated. At runtime, these parts may be replaced by new DIOC fragments from outside the application. DIOC programs are compiled, generating code for each site, in a lower-level language called DPOC. We formalise both DIOC and DPOC semantics as labelled transition systems and prove the correctness of the compilation as a trace equivalence result. As corollaries, DPOC applications are free from communication deadlocks and races, even in presence of runtime updates.Comment: Technical Repor

Type Inference for Deadlock Detection in a Multithreaded Polymorphic Typed Assembly Language

We previously developed a polymorphic type system and a type checker for a multithreaded lock-based polymorphic typed assembly language (MIL) that ensures that well-typed programs do not encounter race conditions. This paper extends such work by taking into consideration deadlocks. The extended type system verifies that locks are acquired in the proper order. Towards this end we require a language with annotations that specify the locking order. Rather than asking the programmer (or the compiler's backend) to specifically annotate each newly introduced lock, we present an algorithm to infer the annotations. The result is a type checker whose input language is non-decorated as before, but that further checks that programs are exempt from deadlocks

Deadlocks and waiting times in traffic jam

In a city of right moving and upmoving cars with hardcore constraint, traffic jam occurs in the form of bands. We show how the bands are destroyed by a small number of strictly left moving cars yielding a deadlock phase with a rough edge of left cars. We also show that the probability of waiting time at a signal for a particular tagged car has a power law dependence on time, indicating the absence of any characteristic time scale for an emergent traffic jam. The exponent is same for both the band and the deadlock cases. The significances of these results are discussed.Comment: 8 pages including 4 eps figures, one in colour, uses revtex to appear in Physica

Sound Static Deadlock Analysis for C/Pthreads (Extended Version)

We present a static deadlock analysis approach for C/pthreads. The design of our method has been guided by the requirement to analyse real-world code. Our approach is sound (i.e., misses no deadlocks) for programs that have defined behaviour according to the C standard, and precise enough to prove deadlock-freedom for a large number of programs. The method consists of a pipeline of several analyses that build on a new context- and thread-sensitive abstract interpretation framework. We further present a lightweight dependency analysis to identify statements relevant to deadlock analysis and thus speed up the overall analysis. In our experimental evaluation, we succeeded to prove deadlock-freedom for 262 programs from the Debian GNU/Linux distribution with in total 2.6 MLOC in less than 11 hours