The Permit based Locking design pattern provides fast acquisition and release of locks without network communication even in distributed systems build around a central lock server. Instead of plain locks, the server manages "permits to lock", and passes them to those clients which probably need the lock next. If a client hosts a permit, the associated lock can be acquired immediately without se...

SaaS is a perfect technology to achieve scale economy. It uses multi-tenant to allow database to share storage but with irregular load, untraceable transaction characteristics and so on. TOL mechanism provides one granularity between the upper coarse-grained granularity and the lower finegrained granularity for each tenant. But the granularity may not be the most suitable. We define the cluster...

In this paper we present a new logical clock, the barrier-lock clock, whose conception was based on the needs of relaxed consistency DSM systems. Barrier-lock clocks can be used to implement timestamp-based relaxed consistency DSMs since they precisely control the partial order of synchronization operations. The size of barrier-lock clocks does not depend on the number of processors of the syst...

1 The PLL (Phase Lock Loop) can synchronize with a deterministic input wave or with a random input symbols. In the first case we have a WPLL (Wave Phase Lock Loop) and in the second case we have a SPLL (Symbol Phase Lock Loop. The WPLL (Wave Phase Lock Loop) is also known as WLL (Wave Lock Loop) or only PLL (Phase Lock Loop). The SPLL (Symbol Phase Lock Loop) is also known as SLL (Symbol Lock L...

Hybrid electric vehicles employ a hydraulic braking system and a regenerative braking system together to provide enhanced braking performance and energy regeneration. In this paper an integrated braking system is proposed for an electric hybrid vehicle that include a hydraulic braking system and a regenerative braking system which is functionally connected to an electric traction motor. In the ...

In this paper, we present the PR-lock, a prioritized spin-lock mutual exclusion algorithm for real time systems. The PR-lock is a contention-free spin lock, in which blocked processes spin on locally stored or cached variables. In contrast to previous work on prioritized spin locks, our algorithm maintains a pointer to the lock holder. As a result, our spin lock can support priority inheritance...

Highly concurrent and reliable data objects are vital for parallel programming. Lock-free shared data objects are highly concurrent and guarantee that at least one operation, from a set of concurrently executed operations, finishes after a finite number of steps regardless of the state of the other operations. Lock-free data objects provide progress guarantees on the object level. In this paper...

introduction: direction and latency of electrical connectivity between different sites of brain explains brain neural functionality. we compared efficiency of cross correlation and phase locking methods in time lag estimation which are based on local field potential (lfp) and lfpspike signals, respectively. methods: signals recorded from mt area of a macaque’s brain was used in a simulation app...

From a project on upgrading an existing commercially used operating system for support of a distributed system architecture, we present results and experience from a comprehensive analytical performance evaluation of a large number of different implementation strategies for distributed lock management. The various lock management policies we consider differ in the management of the lock databas...